Michael Cisneros

September 14, 2013

Adv. Nutrition

Research Review # 1

Reference

Sawyer, Jason C., Richard J. Wood, Patrick W. Davidson, Sean M. Collins, Tracey D. Matthews, Sara M. Gregory, and Vincent J. Paolone. "Effects of a Short-Term Carbohydrate-Restricted Diet on Strength and Power Performance." Journal of Strength & Conditioning Research 27.8 (2013): 2255-2262. Web. 14 Sept. 2013

Purpose of Study

The Purpose of the study was to examine the effects of switching from a habitual diet to a carbohydrate-restricted diet on strength and power performance in trained men (n=16) and women (n=15).

Methods and Materials

This study used a repeated measures design to determine the effect of consuming a CRD on strength and power compared with a habitual diet. To assess the changes in strength and power, each subject performed a battery of tests (described in the following) while consuming his or her habitual diet for 7 days and again after consuming a CRD for 7 days. The tests administered consisted of the following: hand dynamometry, countermovement vertical jump, 1RM bench press and back squat, maximum-repetition bench press, and 30-second Wingate anaerobic bicycle test. The independent variables were gender and diet. The dependent body mass variables were body weight (kg), fat-free mass (FFM; kg), fat mass (kg), percent body fat, and total body water (TBW; kg). The dependent dietary variables were total kilocalories, carbohydrate (g), fat (g), and protein (g). The mean values for total kilocalories, carbohydrate, fat, and protein during the habitual diet and CRD were used to calculate differences. The dependent strength and power variables included handgrip strength, countermovement vertical jump, 1RM bench press and back squat, maximum-repetition bench press, and 30-second Wingate anaerobic cycling test.

Each subject performed 2 testing sessions. The first testing session occurred after each subject consumed a habitual diet for 7 days. After the first testing session, the subjects began the CRD. The second testing session occurred after each subject had consumed a CRD for 7 days. Before each testing session, subjects were required to refrain from performing resistance exercise for 48 hours. Alcohol was not consumed for the duration of the study. Subjects were instructed to refrain from consuming caffeine for 12 hours before each testing session. Participants arrived at the Human Performance Laboratory after a 12-hour fast between the hours of 6:00 and 8:00 AM. Weight and body composition were measured using the Tanita BC 418 Segmental Body Composition Analyzer (Tanita, Tokyo, Japan). The subject was then provided with a pretesting meal and, after consumption of the meal, was instructed to return to the testing laboratory after 2 hours. The pre-exercise meal was provided to each subject 2 hours before the start of each exercise testing session. The meal consisted of 400 kcal. The meal included 250 ml of water, 2 hard-boiled eggs, 28 g of cheddar cheese, and a protein shake (Advant Edge Whey Protein; EAS, Inc., Abbott Park, IL, USA). The individuals that regularly consumed caffeine were allowed to consume 300 ml of coffee with 15 ml of cream. To ensure that the breakfasts were iso-caloric, kilocalories consumed in coffee were deducted from the protein shake. Subjects were allowed to drink water during the 2 hours after breakfast and during the entire exercise testing session.

Results

After the change of diet, strength for the handgrip and back squat increased after consuming the CRD diet. There was no significant change in the bench press. Subjects had a significant increase in vertical jump height while consuming the CRD compared with the habitual diet. Keiser power output while consuming a CRD had no significant difference. Subjects experienced an overall decrease in total body mass after consumption of a carbohydrate-restricted diet.

Critique of the Study

Most of the subjects were accustomed to movement patterns associated with the study. The 1-week period between the changes in diet is not a significant enough difference to allow for any physiological adaptation. For this reason, the study’s results showed an insignificant difference in performance. However, a one-month or two-month period of the CRD diet may result in differences in body composition and performance. The study itself has great potential, however, just needs a longer time period to show distinct performance differences.

Practical Application

The results of this study indicated that a 7-day CRD was effective for reducing body weight with no decrement in strength and power performance. These findings may have implications for sports that use weight classes, and in which strength and power are determinants of success. Wrestling, boxing, and powerlifting are examples of sports included in this category. Individuals participating in these types of sports could use a CRD 7 days before competition to lose necessary body weight and have no detriment in strength and power. A CRD could be used to replace potentially dangerous weight reduction strategies currently employed by some athletes, including starvation and extreme dehydration.

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Thread:: Estimation of Prepractice Hydration Status of National Collegiate Athletic Association Division 1 Athletes
Post:: Estimation of Prepractice Hydration Status of National Collegiate Athletic Association Division 1 Athletes
Author:: Jamie Duke

Posted Date:: September 22, 2013 7:10 PM
Status:: Published

Jamie Duke
KINE 5306
Research Review 1

Estimation of Prepractice Hydration Status of National Collegiate Athletic Association Division 1 Athletes

Reference:
Volpe, S., Poule, K., Brand, E. (2009). Estimation of Prepractice Hydration Status of National Collegiate Athletetic Association Division 1 Athletes. Journal of Athletic Training, 44(6): 624-629

Purpose of the Study:
The purpose of this study was to find the hydration status of collegiate athletes prior to practice, using a urine specific gravity test, and the factors that influence this. With this a comparison can be made between male and female athletes, as well as studying the effects of menstruation on female hydration.

Methods and Materials:
A group of 263 student athletes (138 males, 125 females) from an NCAA Division I university in New England were asked to participate in a study regarding pre-practice hydration. One spontaneously void urine sample was taken from each participant approximately one hour prior to practice (with the majority of practices beginning around 4:00pm.) The samples were read using a refractometer and placed into a specific gravity category. The urine specific gravity categories were as follows: Euhydrated (specific gravity of less than 1.020), Hypohydrated (specific gravity of 1.020-1.029), Significantly Hypohydrated (specific gravity equal to or more than 1.030).
The student athletes were also given a Fluid Intake Questionnaire to further assess hydration education. The subjects also reported their body mass and height. On this questionnaire females were also asked questions regarding menstrual history in order to discover the effects of menstruation on hydration.

Summary of Results/Conclusion:
13% were Significantly Hypohydrated (mean urine specific gravity of 1.031+/- 0.002). 53% were Hypohydrated (mean urine specific gravity of 1.024 +/- 0.003). The remaining 34% were Euhydrated (mean urine specific gravity of 1.012 +/- 0.005). Of the Hypohydrated, 47% were male and 28% female. There was no significant difference in female hydration due to menstruation. According to the self-reported fluid intake women reported drinking an average of 53 fl oz, and men reported drinking an average of 51 fl oz.

Critique of Study:
This study was very informative of hydration practices among NCAA Division I athletes. Perhaps this is due to lack of hydration education. It may also be due to liquid intake which has a negative effect on hydration such as caffeinated drinks. Many athletes may have a misunderstanding of what is means to be hydrated, which can lead to the athlete assuming they are hydrated when in fact they are not. They may also misunderstand the effects of dehydration, such as cardiovascular strain, which can result in a decrease in performance.

Practical Application:
This study brings to light that athletes are not properly hydrating prior to practices. It also suggests that these athletes, and perhaps coaches, are not educated on hydration and the importance to athletic performance. Perhaps putting urine color charts in locker rooms would assist in this education. Also, educating coaches and encouraging them to set up a water intake schedule for their athletes may increase the percentage of athletes who are hydrated.

It would be interesting to do a study of the effects of hydration on specific sport performance.

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Thread:: Eating at fast-food restaurants is associated with dietary intake, demographic, psychosocial and behavioural factors among African Americans in North Carolina.
Post:: Eating at fast-food restaurants is associated with dietary intake, demographic, psychosocial and behavioural factors among African Americans in North Carolina.
Author:: Takisha Edwards

Posted Date:: September 22, 2013 7:51 PM
Status:: Published

Research Review Number One

Title

Eating at fast-food restaurants is associated with dietary intake, demographic, psychosocial and behavioural factors among African Americans in North Carolina.

Purpose of Study

This study served two purposes: 1. to describe the prevalence of eating at fast-food restaurants among African American adults in North Carolina; and 2. To examine cross-sectional associations of eating at fast-food restaurants with dietary intake and demographic, behavioral, and diet-related psychosocial factors in this population.

Methods and Materials

In this particular self-report study, an 11-page questionnaire was sent to 4276 African American persons who were chosen at random from the North Carolina Department of Motor Vehicles roster. Participants were given the option to complete the survey via mail-in, over the phone, or online. The questionnaire used covered the following areas: demographic characteristics, behavioral and lifestyle factors; diet-related psychosocial factors; dietary intake; and eating at fast-food restaurants. The results of only those who responded were then analyzed.

Summary of Results/Conclusion

This study found a positive and linear relationship between the frequency of eating at fast-food restaurants and total fat and saturated fat intakes in addition to fat-related dietary behaviors. This study also found there to be an inverse relationship between the frequency of eating at fast-food restaurants and vegetable consumption.

Critique of Study

I found this study to be very interesting, I only wish a more recent study similar to this (aimed at the African American demographic) was available. Being African American with lots of family from the South, I see these diet practices firsthand. Oftentimes, the nearest grocery store is across town. Not that that is an excuse, but grocer locations make a difference in homes where the elderly can’t drive. This study quantifiably confirmed what I already qualitatively knew. I am curious as to how far the respondents lived from a grocery store or at least a convenience store that sold a few fresh fruits and vegetables. Because this was a self-report study, I also can’t help but question how honest the respondents were, or if the Hawthorne effect was an issue.

Practical Application(s) of the Study

This study and others like it can be used to help develop awareness and prevention campaigns in areas where there is a severely disproportionate ratio of fast-food eateries to grocery stores. Also, we can generalize the results of this study and apply them to other demographics, especially high school and collegiate athletes who often love eating at fast-food restaurants. Education on dietary recommendations are beneficial for everyone, not just one group of people. A simple and basic rule that most know, but not always practice is to eat fast-food in moderation.

Unanswered Questions

1. What were the occupations of the respondents, if any?

2. For the respondents who answered ‘no’ when asked if they believed there was a relationship between diet and cancer, what was their reason for their answer?

3. How far away was the nearest grocery store from the respondents?

Article

Satia, J. A., Galanko, J. A., & Siega-Riz, A. M. (2004). Eating At Fast-food Restaurants Is Associated With Dietary Intake, Demographic, Psychosocial And Behavioural Factors Among African Americans In North Carolina. Public Health Nutrition, 7(08), 1089-1096.

Attachment: File

Article 1.pdf (116.487 KB)

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Thread:: The influence of commercially-available carbohydrate and carbohydrate-protein supplements on endurance running performance in recreational athletes during a field trial
Post:: The influence of commercially-available carbohydrate and carbohydrate-protein supplements on endurance running performance in recreational athletes during a field trial
Author:: Cody Knight

Posted Date:: September 22, 2013 11:54 PM
Status:: Published

Cody Knight

KINE 5306 – Advanced Nutrition

Dr. Kelly Brooks

22, September 2013

The influence of commercially-available carbohydrate and carbohydrate-protein supplements on endurance running performance in recreational athletes during a field trial

Reference:

Coletta, A., Thompson, D., & Raynor, H. (2013). The influence of commercially-available carbohydrate and carbohydrate-protein supplements on endurance running performance in recreational athletes during a field trial. Journal of the International Society of Sports Nutrition, 10(1), 17.

Purpose of the Study:

The purpose of this study was to compare carbohydrate-protein (CHO-P) supplementation to the traditionally used CHO supplementation during endurance exercise. The research was conducted as a field study, to replicate real-life conditions in order to elicit more practical outcomes for the recreational endurance athlete.

Methods and Materials:

Twelve male recreational runners completed four, 19.2km time trial (TT) runs. The subjects were to perform at a pace similar to racing conditions, which included a final sprint to the finish of 1.92km. Supplementation was provided before the start of the run (120ml) and then in 4km increments (600ml total). Performance was measured by time to complete the run and also the final 1.92km sprint. Every subject performed a TT with each supplementation. The supplements used were Gatorade (as the CHO) and Accelerade (as the CHO-P). A third caloric supplement, double carbohydrate (CHO-CHO) was tested in order to match the CHO-P supplement in calories. This was done because both the CHO and CHO-P supplements were matched in carbohydrate content. The placebo (PLA) used was Crystal Light. All participants complied with pre-test protocol and met criteria of the study. Body composition and VO2max tests were conducted to describe participant characteristics. Once the tests were completed, the first run was scheduled no more than one week after the initial session. Prior to each run, participants submitted a 24 hour diet/exercise record of all caloric intake and aerobic exercise during the 24 hours before the run. Diet and exercise remained consistent before all TT. Each trial was scheduled 7-10 days apart. Weather conditions were measured on site of each trial and the participants performed on a closed, paved running trail.

Summary of Results and Conclusions:

Results from the study concluded that commercially available CHO and CHO-P supplements do not appear to enhance performance in male recreational runners performing runs greater than 60 minutes. Additionally, the supplements did not enhance performance above that of the PLA. The results from the study were determined through analysis of no difference in time to complete the run or the final sprint to the finish.

Critique of the Study:

Research conducted within a field trial under applied, real life conditions is appreciative because they usually result in more practical outcomes. I do not believe that the outcome would have changed with more participants, but only having twelve can certainly leave room for debate.

Practical Applications of the Study:

This investigation was conducted to simulate real-life competitive conditions. Supplements were compared within trials using an outdoor course. This research is useful because of the rising trend among endurance athletes to use CHO-P supplementation, as opposed to CHO supplementation.

Questions:

I realize that the performance would naturally decline with only 7-10 days between each trial, but given more time to recover between trials, would the outcome change if the trial were of longer distance?

http://www.jissn.com/content/10/1/17

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Thread:: Research Review 1
Post:: Research Review 1
Author:: John Lerma

Posted Date:: September 14, 2013 8:17 PM
Status:: Published

John Lerma

KINE 5306 Adv Nutrition

September 14, 2013

Research Review #1

Reference

Kruszewski, M. (2011). Changes in Maximal Strength and Body Composition After Different Methods of Developing Muscle Strength and Supplementation With Creatine, L-Carnitine and HMB. Biology Of Sport, 28(2), 145-150.

Purpose of Study

The purpose of the study was to examine the effects of supplementation with creatine, L-carnitine, and HMB coupled with various methods of developing muscular strength on maximal strength and body composition.

Methods and Materials

Young male competitors recruited to participate were divided into the following groups: L-CAR – beginners (n = 63) practicing bodybuilding training and receiving L-carnitine (n=30) or placebo (n=33); CRE – advanced powerlifters (n=38) practicing weightlifting training and receiving creatine (n=16) or placebo (n=22); and HMB – beginners practicing isometric training (n=69) and receiving HMB (n=35) or placebo (n=34). Maximal strength was estimated in powerlifting exercises (squat, bench press, and deadlift) but obtaining a one-rep max, and their statistical significance within groups as well as inter group interactions was assessed. Subjects declared no other supportive substances would be taken other than those selected for the study. Body composition was evaluated by lean body mass, fat content, and water content, all of which are estimated using bioelectrical impedance.

For statistical analysis of the results, student’s t-test for dependent variables was used. Statistical significance of differences between mean values and analyzed variables were assessed using ANOVA with repeated measurements.Statistical significance of changes between repetitions was estimated using the Wilcoxon test, while statistical significance of the increments depending on the group was estimated using the Mann-Whitney U test. All described calculations were performed using STATISTICATM 5.5 package.

Summary of Results/Conclusions

In regards to L-Carnitine and its effects on body composition, no significant changes in either fat or water content was observed. In regards to creatine use and its effects on body composition in powerlifters, the results were unexpected. Its use led to a significant decrease in fat content. In regards to HMB supplementation and its effects on body composition and strength. It led to increases in lean body mass and decreases in water content in the body. In summary, supplementation of HMB appears to provide the most effective support for developing maximal strength and body composition improvement. All three supplements benefited maximal strength, but their effects on body composition are controversial.

Critiques of the Study

I believe the study was well thought out and designed appropriately for the research question. The findings are also interpreted within the context of other studies and theory, which is common in research. The description of the data analysis is more than adequate, as well. It also seems that the conclusion is justified given the conduct of the study.

Practical Applications of the Study

The results of this study indicated that creatine supplementation led to significant reductions in fat content and increases in water content in advanced powerlifters. These changes may suggest that in advanced strength athletes, the effects of creatine may be much more far-reaching than indicated by manufacturers. This may be something to note for strength athletes who compete in weight classes. Perhaps creatine supplementation in combination with a high-protein, low-fat diet may induce greater reductions in fat content. I would like to see further research done with HMB supplementation coupled with various training methods in elite level athletes or strength athletes.

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Thread:: RR1: Hydration
Post:: RR1: Hydration
Author:: Ramiro Lopez

Posted Date:: September 22, 2013 8:54 PM
Status:: Published

Attachment: File

RR 1.docx (20.084 KB)

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Thread:: The Effects of Creatine Supplementation on Sprint Performance and Selected Hormonal Responses
Post:: The Effects of Creatine Supplementation on Sprint Performance and Selected Hormonal Responses
Author:: Vickie Machen

Posted Date:: September 14, 2012 8:35 PM
Status:: Published

The Effects of Creatine Supplementation on Sprint Performance and Selected Hormonal Responses

Citation:

Faraji, H., Arazi, H., Sheikholeslamivatani, D., & Hakimi, M. (2010). The Effects of Creatine Supplementation on Sprint Running Performance and Selected Hormonal Responses. South African Journal for Research in Sport, 32(2): 31-39.

Purpose:

The purpose of this study is to determine the influence of short-term creatine supplementation and circulating hormone concentrations on sprint running performance for the 100 and 200-meter dash.

Methods/Materials:

Twenty amateur male runners were divided into two different groups, the placebo group and the creatine supplementation group. The creatine group were given three equal dosages of capsules filled with creatine monohydrate supplementation of 20g/day. This was to be taken with every major meal. While the placebo group was provided with an identical powdered cellulose placebo. The subjects were tested before and after six days for resting blood hormone concentrations and performance.

Summary of results/conclusion:

The men who received creatine supplementation had a significant decrease in their time for the 100-m run, but not in the 200-m. The conclusion of the study found that short-term creatine supplementation improved sprint performance in the 100 meter dash, but there was no hormonally medicated performance improvement.

Critique of the study:

The study was well organized, and displayed a fair amount of information. There are a few changes I would make to this experiment. I would include females in the experiment. I would also make the experiment have a longer duration period, instead of just six days. This way you would be able to take more data and see if the creatine supplementation would work for the 200-m run, if there was a longer time duration.

Practical Application of the Study:

This study can be used to help coaches decide if they feel it would be best for their athletes take a creatine supplement, especially for the short distance sprinters. I feel that creatine would help an athlete increase their performance. It has many benefits, and should be used with the help of an expert.

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Thread:: MRI Evaluation of Body Composition in Wrestlers during Rapid Weight Loss
Post:: MRI Evaluation of Body Composition in Wrestlers during Rapid Weight Loss
Author:: Vickie Machen

Posted Date:: September 14, 2012 3:09 PM
Status:: Published

RESEARCH REVIEW #1: Advanced Nutrition

A. Source

Kukidome, T., Shirai, K., Kubo, J., Matsushima, Y., Yanagisawa, O., Homma, T., Aizawa, K., (2008). MRI evaluation of body composition changes in wrestlers undergoing rapid weight loss. British Journal of Sports Medicine. (48), pp.814-818.

B. Purpose of Study

The purpose of this study was to evaluate the changes in body composition of college wrestlers undergoing rapid weight loss over time using magnetic resonance imaging (MRI).

C. Methods and Materials

The study used 12 male wrestlers between 18-22 years of age participating in an intercollegiate tournament. Measurements were taken from each athlete at five separate times through the course of the study; 1 month and 1 week prior to weigh-in, on the day of the weigh-in, on the day of the match (after the match) and 1 week after the weigh-in. These measurements included body weight, body fat percentage, body water content, and a MRI of the trunk and right femoral region. However the authors did not list how this data was specifically collected. In addition, a registered dietitian conduced a survey on food intake combining methods of a self-report, and visual records (digital photo). The pre-1 month survey was conducted a month before weigh-in, the pre-1 week survey was conducted a week before weigh-in, the third was taken the day of the weigh-in, and the final survey was taken at some point after weigh-in and after the match on competition day.

A 1.5T MRI system was used to measure the cross-sectional areas of muscles, subcutaneous fat and viscera (in trunk) in the femoral region and trunk regions. The muscle area of the lower extremity was defined as the cross-sectional area of the total muscles from the knee joint gap to the superior end of the greater trochanter (8 muscles, see article). The same data was collected in the trunk region, which was defined by the cross-sectional areas of total muscles (8 muscles, see article).

D. Summary of Results/Conclusion

After collection, data was compared through the use of a one-way analysis of variance (ANOVA), and when a significant difference was found the Fisher’s protected least significant difference multiple comparison test. The significance was set at p<0.05. The results of body composition data revealed there was no change in body weight between 1-month and 1 week before weigh-in, but it was significantly lower (average 5.4kg or 9.9lbs) on the day of weigh-in compared to 1-month before (p<0.01). In addition to that, they average percentage of body weight reduction was -7.3%. The day of competition (after the match) body weight data increased an average of 3.1kg (6.8lbs) compared to the day of weigh-in. The fat percentage and body water content was also significantly lower on the day of weigh-in compared to 1-month before (p<0.05 and p<0.01, respectively). However, 1-week after the weigh-in they had returned to the same levels as 1-month before. The MRI revealed the cross-sectional areas of total muscles and fat in the trunk and lower extremities were significantly lower at 1-week before weigh-in, the day of weigh-in, day of competition, and 1-week after weigh-in compared to 1-month prior (p<0.01). Interestingly, the cross-sectional levels at 1-week after the weigh-in reverted to the same ones seen 1-week prior to weigh-in. However, the lower extremities did not show a significant difference between 1-week after weigh-in and 1-month prior. It is important to note, the cross-sectional areas of fat in the lower extremities the day of competition reverted back to the same levels seen 1-month prior to weigh-in. Moreover, the fat in the lower extremities was significantly higher 1-week before weigh-in than 1-month prior (p<0.05). These two pieces of information revealed that there are differences found in skeletal muscle and fat tissue properties, depending on the different regions of the body during the body composition changes seen during rapid weight reduction in the wrestlers. Further research is needed to find the degree of change that occurs.

To summarize the survey, the athletes showed an obvious decrease in food and fluid intake from 1-month before weigh-in all the way up to the day of the way in. However, the time period between weigh-in and competition revealed their food and fluid intake was 1.5 times the amount reported 1-month prior. The authors speculated the body composition on the day of competition reverting back to that seen 1-week prior to weigh-in is a result from the observed increase of food and fluid intake during the time between weigh-in and the day of competition. This would suggest that nutrient intake and rehydration are two major factors that should be included into the planning of wrestlers’ strength and conditioning periodization programs, especially in the recovery process between weigh-in and competition.

E. Critique of Study

I personally enjoyed this study because the use of MRI gives new insight as to what is actually occurring with body composition during rapid weight loss methods over-time. The pairing of the MRI a nutritional survey is very unique and has revealed new roads to research for other sports. The statistical methods they used for analyzing data seemed to be sufficient. However, I was disappointed that the authors did not list the methods or tools used to gather the body composition data (body water content, percent body fat, and body weight). Also, there was not any discussion about the observation that the cross-sectional area of fat in the lower extremities was significantly higher (p<0.01) 1-week before to the weigh-in compared to 1-month prior. In my opinion, this alerted my attention because the wrestlers were taking in much less food and fluid by this point before competition, and should had a decrease in fat mass. It is understood that there could be many explanations for this, but the authors never discussed it.

F. Practical Application

To practically apply this study to the real world or my own career I could do one or several of the following:

- Run this exact same study on Mixed Martial Arts (MMA) fighters.

- Apply this information to current MMA athletes, or any other athletes in sports the use rapid weight loss methods.

- Use this as support to any seminars or discussions I have with fighters or coaches who use rapid weight reduction methods.

- Coaches of all sports using this method of weight loss can pay more attention to the nutritional and hydration behaviors of their athletes so performance can be improved during competition.

Attachment: File

RESEARCH REVIEW #1 advanced nutrition.docx (132.936 KB)

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Thread:: Half-Marathon and Full-Marathon Runner's Hydration Practices and Perceptions
Post:: Half-Marathon and Full-Marathon Runner's Hydration Practices and Perceptions
Author:: Vickie Machen

Posted Date:: September 14, 2012 2:32 PM
Status:: Published

Research Review #1

O'Neal, E. K., Wingo, J. E., Richardson, M. T., Leeper , J. D., Neggers, Y. H., & Bishop, P. A. (2011). Half-marathon and full-marathon runners' hydration practices and perceptions. Journal of Athletic Training,46(6), 581-591.

Purpose of Study

Among the scientific community there has yet to be a consensus as to what hydration guidelines distance runners should follow. Due to the lack of study, what little information distance runners do encounter varies greatly. In doing so, the primary purpose of this study was to determine which beverages runners drink and why, whether decreased performance or heat-related illness symptoms are believed to be caused by lack of hydration, and how runners monitor their hydration status. To conduct this investigation, populations representing “average” nonelite level distance runners were targeted (O'Neal, Wingo, Richardson, Leeper, Neggers & Bishop, 2011). A questionnaire that consisted of 23 items was used for the survey.

Methods and Materials

Participants in the 2010 Little Rock, Arkansas, Half-Marathon and Marathon were surveyed on site during exhibition two days before the race. There were no qualification time requirements needed to attend the marathon which therefore brought a large number of possible participants. The only inclusion criteria for this study were that participants be at least 18 years of age and registered to run the half-marathon or full marathon (O'Neal, Wingo, Richardson, Leeper, Neggers & Bishop, 2011). A total of 146 men and 130 women were part of the investigation.

Pertaining to materials, investigators provided a table for participants to complete their surveys as well as multiples signs that informed runners of their study located at the entrance of the registration site. Investigators had also gone on further by approaching runners to explain the survey and what requirements were needed if they wished to be a part of the study.

Summary of Results/Conclusion

According to results, 70% percent of all participants believed that decreases in their performance were the effects from dehydration. Furthermore, the high group participants reported an increasing rate than those of the low and moderate leveled groups. In terms of choice of beverage, the high group reported greater use of sports beverages and believed that sport beverages containing carbohydrates and electrolytes in runs greater than an hour improves performance better than water alone. This may be the result of the group having greater experiences in terms of distance, intensity, and frequency than that of a runner from the low or moderate group. When monitoring hydration statuses, the majority of distance runners used urine color. This simple technique correlates highly with urine specific gravity and urine osmolality and is a practice supported by the National Athletic Trainers Association (O'Neal, Wingo, Richardson, Leeper, Neggers & Bishop, 2011).

There is a possibility that because the majority of distance runners trained without any form of supervision it is weighed heavily on the importance of health care professionals to pass information to fellow runners of proper hydration in training and competition. Ranging from expositions to word of mouth is suggested. The measuring of changes in body mass is the most accurate way to determine acute changes in hydration level and sweat loss and is a vital component for developing an individual hydration strategy (O'Neal, Wingo, Richardson, Leeper , Neggers & Bishop, 2011). According to this study, only 5 (2%) reported to using this form of measurement as a hydration status. It is clear that forms of promotion is needed as well as further studies on ways to be able to develop individualized hydration plans for both recreational and elite-leveled distance runners.

Critique of the Study

A notable strength found within the study was the survey created by the lead investigator, Dr. O’Neal. Before reaching the hands of participants, the survey went through various stages of revision. Co-investigators, whom were research experienced in areas related to this one, checked the content before presenting it to a review panel consisting of experienced runners and registered dieticians. Additionally, a draft survey was given to a group of runners to report if there were any sections that needed clarification.

As there is strength in conducting a survey there are also weaknesses that need to be noted. There is a possibility that participants were not as truthful as investigators would have liked them to be. Another weakness found within the article is the location of where investigators performed the study. Variables including climate could have changed the results had it been conducted in areas where it is normally cool and arid than in an area where it is common to be hot and humid like in Little Rock and the prevalence of dehydration or heat-related illnesses could possibly be greater.

Practical Application(s) of the Study

It is to be noted that the survey was conducted on “average” distance runners and results cannot be used over to elite-level runners. However, it may give great insight to possibilities of creating personal hydration guidelines that higher level runners can use. According to the study, the high group of participants had a greater percentage in experiencing decreased performance and reports of heat-related illnesses believed to be by dehydration. It may due to the increased level of intensity, distance, and frequency than those of the low or moderate groups. None the less, the safety of distance runners should be taken into accord in terms of fluid intake being a preventive measure for dehydration and heat-related illnesses. Additionally, applications can also be placed upon younger athletes who wish to pursue distance running. Education about proper hydration in training and competition can be of great attribute.

Questions:

What are the statistics in incidents of dehydration and heat-related illnesses in elite-level distance runners?

Is there are common outline that many athletes/coaches are using (if any) when training?

What tests are agreed by consensus in the scientific community to be an accurate way to determine hydration status and sweat loss among distance runners? How can it be implemented in a hydration plan?

Attachment: File

Review Article #1.pdf (1.066 MB)

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Thread:: Effects of supplemental fish oil on resting metabolic rate, body composition, and salivary cortisol in healthy adults
Post:: Effects of supplemental fish oil on resting metabolic rate, body composition, and salivary cortisol in healthy adults
Author:: Vickie Machen

Posted Date:: September 13, 2012 11:01 PM
Status:: Published

Noreen, E. E, Sass,M.J., Crowe, M.L., Pabon, V.A., Brandauer, J., Averill, L.K. (2010). Effects of supplemental fish oil onresting metabolic rate, body composition, and salivary cortisol in healthyadults. Journal of the International Society of Sports Nutrition, 7:31

The purposes ofthe study was to determine the effects of supplemental fish oil on bodycomposition and resting metabolic rate (RMR) in healthy adults and the effectsof supplemental fish oil on morning salivary cortisol concentrations, anddetermine if there is a relationship between changes in body composition due totreatment.

The studyconsisted of 44 participants (men and women) that were healthy and active, butnot engaged in a consistent, systematic exercise program. These subjects were randomly assignedin a double blind manner to a group that was given safflower oil (SO) or Fishoil (FO). In addition, they weredirected to consume two capsules with breakfast and two capsules with dinnerfor a six-week period. The testingbegan after a morning following ten-twelve hour overnight fast, in which, RMRwas determined in twenty four participants (the first twelve from each group)using an open circuit indirect calorimetry, body composition was assessed viathe Bod Pod of all participants, and salivary samples were taken via passivedrool to be analyzed for cortisol content using an enzyme immunoassay kit. Lastly, all the testing was repeatedafter a six-week period.

The resultspresented with a significant increase in fat free mass following treatment of FOcompared to SO (FO=+0.5kg, SO=-0.1kg, p=0.03), a significant reduction in fatmass (FO=-0.5kg, SO=+0.2kg, p=0.04), and a tendency for decrease in body fatpercentage (FO=-0.4% body fat, SO=+0.3% body fat, p=0.08). However, no significant differences wereobserved for body mass (FO=0.0kg, SO=+0.2kg), RMR (FO=+17kcal, SO=-62kcal), orrespiratory exchange ratio (FO=-0.02, SO=+0.02). Lastly, there was a tendency for salivary cortisol todecrease in the FO group (FO=-0.064μg/dL,SO=+0.016μg/dL,p=0.11) and there was a significant correlation in the FO group between changein cortisol and change in fat free mass (r=-0.504, p=0.02) and fat mass(r=0.661, p=0.001). Consideringall the data, this study showed that six weeks of supplemental fish oilincreased lean mass and reduced fat mass in healthy adult. Along with decreasing salivary cortisolconcentrations, which contributed to the increase of fat free mass anddecreased fat mass observed.

Within the studythere appeared to be some areas of weakness that could be critiqued, such as,the researchers did not use or ask for dietary records of the participants,they tested RMR for twenty-four subjects versus all the subjects, and they didnot test systematically active individuals (athletes). Chiefly, an application of this studywould be to introduce fish oil supplementation to overweight individuals andindividuals wanting to decrease fat mass and increase lean mass.

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Thread:: Comparison of coconut water and a carbohydrate-electrolyte sport drink on measures of hydration and physical performance in exercise-trained men
Post:: Comparison of coconut water and a carbohydrate-electrolyte sport drink on measures of hydration and physical performance in exercise-trained men
Author:: Vickie Machen

Posted Date:: September 13, 2012 3:38 PM
Status:: Published

Jasmine Richmond

KINE 5306

9/10/12

Research Review 1

A. Kalman, D. S., Feldman, S., Krieger, D. R., & Bloomer, R. J. (2012). Comparison of coconut water and a carbohydrate-electrolyte sport drink on measures of hydration and physical performance in exercise-trained men. Journal of the International Society of Sports Nutrition, 9(1).

B. The purpose of this study was to investigate the effects of coconut water and a carbohydrate-electrolyte sports drink on hydration status and physical performance in exercise-trained men.

C. Subjects had to be exercise-trained, meaning that they had been engaged in a physical activity program for the past 6 months and didn’t have difficult walking/running on a treadmill. 12 males were deemed eligible given the previously mentioned requirements and by completing a Physical Readiness Questionnaire. All subjects were told to maintain their exercise and nutritional regimens with the exception of not exercising 24 hours prior to testing sessions and fasting (nothing but water after midnight) prior to testing. Upon arrival to the lab on each of the four testing days, each subject was given a standardized breakfast and 470ml of water. Each testing session consisted of a dehydrating exercise test, a rehydration period, and a performance exercise test. The dehydrating test consisted of two, 30-minute bouts of walk/jogging on a treadmill with a 10-minute ret interval between the two. The bouts were broken down into 5 minute segments are 0% incline at speeds of 2,3,4,5,6 and 7 miles per hour (mph). After this test the following variables were tested for: body mass, plasma osmolality, urine specific gravity, subjective measures, heart rate, and blood pressure. These measurements were also collected pre-test to establish a baseline. Once the previous mentioned variables were collected the subject was given their assigned beverage in a single-blind design. Over the course of the four testing sessions each subject received each of the beverages, which were: supermarket brand bottled water, pure coconut water, coconut water from concentrate and a carbohydrate-electrolyte sports drink. The amount of the beverage given was determined by the amount of body mass lost during the exercise test. Subjects were allowed 60 minutes to consume their beverage.

The performance test was conducted three hours after the dehydrating test and was performed on a treadmill. A 5-minute warm-up was performed at a self-selected speed at 0% incline, and then the speed went up to 4.2 mph and the grade increased every 3 minutes until volitional exhaustion. Total exercise time was recorded for this test. During the time between the two exercise tests subjects were asked every hour to rate their thirst, bloated-ness, refreshed, stomach upset, and tiredness on a 5-point analog scale.

D. No significant difference was found in total exercise time on the performance test, between the four beverages. The only difference noted among conditions to body mass were between the coconut water from concentrate and bottled water. Body mass was slight greater with the concentrated coconut water compared only to bottled water. This same difference was also found to be true in concern to fluid retention. All four beverages showed effects on the subjective measures taken with the analog scale.

This study was able to determine that coconut water (both natural and from concentrated) provide similar rehydration effects compared to carbohydrate-electrolyte sport drinks. Thus, all are good choices for rehydration, without one causing any more improvement in exercise performance than the other.

E. Some limitations of this study were the small sample size and the fact that only males were involved. The study might have shown different, or more varied results, if more subjects had been involved. Similarly, if the subjects had been both male and female then different results could have been observed. The dehydration exercise could have been performed differently to achieve more dehydration that was accomplished with this protocol as well.

F. Practical application of this study is that when dehydrated the body needs fluid period. Since little difference was found, if any, between the different beverages it supports that notion that water will suffice to accurately rehydrate someone. This is good information for coaches, trainers (personal and athletic), nutritionists, and physicians to know so that they can advise clients/athletes on the best hydration strategy for their needs.

Unanswered Questions:

•&νβσπ;Why were only males’ chosen?

•&νβσπ;Why was the sample size not larger?

•&νβσπ;Why was only plasma osmolality and urine specific gravity used as measures of dehydration? Why weren’t BUN/Cr levels looked at?

Attachment: File

Nut_ArticleReview1.pdf (235.195 KB)

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Thread:: Carbohydrate ingestion and soccer skill performance
Post:: Carbohydrate ingestion and soccer skill performance
Author:: Vickie Machen

Posted Date:: September 13, 2012 1:24 PM
Status:: Published

Ali, A., Williams, C. (2009). Carbohydrate ingestion and soccer skill performance during prolonged intermittent exercise.Journal of Sports Sciences, 27(14): 1499–1508.

There is limited information on the effects of fatigue on skill performance in soccer, which is surprising because the skill elements are essential to win soccer games. The contribution of anaerobic metabolism to provide energy for these skillful actions is critical during a soccer game, as the performance of skills requires powerful movements. Some studies within this context reported a 5% improvement in soccer dribbling performance following carbohydrate supplementation during a 90-min exhibition match. So the aim of this study was to investigate the effect of ingesting a carbohydrate-electrolyte solution, during the 90-min Intermittent Shuttle Test, on soccer skill performance.

Seventeen male soccer players completed two main trials, each separated by 7 days. On the first day they drank one of the test solutions, a sports drink containing 6.4% carbohydrate. In the other trial they drank a non-electrolyte, artificially sweetened placebo that contained no carbohydrate. The participants ingested a volume of fluid equivalent to 8ml/kg of body mass before and then 3ml/kg of body mass after every 15 min of exercise. After ingesting the test solution, the participants completed six 15-min blocks of an intermittent Shuttle Test punctuated by 4-min rest periods. Each 15-min block consists of approximately 11 repeated cycles of walking, running (at a speed equivalent to 95% VO2max), jogging (at a speed equivalent to 55% VO2max), and sprinting. Then they performed the Loughborough Soccer Passing Test in between each block (including pre and post testing).

Performance was significantly slower during the last 30 min than the first 30 min of exercise for both groups. There were no differences between carbohydrate-electrolyte and placebo trials on the performance of the Soccer Passing Test. Examination of the pre- and post-exercise results (i.e. 0 min vs. 90 min) showed a 12% decrease in performance in the carbohydrate-electrolyte trial but a 24% de- crease in the placebo trial, although this was not statistically significant. Although not statistically significant, there was a trend for performance to be better maintained in the carbohydrate-electrolyte trial in the last block of exercise, whereas there was a trend for a further decrease in performance during the placebo trial. Mean estimated carbohydrate oxidation rates were significantly higher in the carbohydrate-electrolyte trial, whereas mean fat oxidation rates were significantly higher in the placebo trial. However, estimated energy expenditure rates were not different between trials. In summary, soccer skill performance appears to decline during the last 15 min of exercise within the 90-min intermittent running test. For this test, supplying carbohydrate during exercise did not provide any further benefits in terms of maintaining skill and sprint performance. Nevertheless, it is important to note that the provision of carbohydrate appears to induce metabolic and perceptual benefits relative to when no carbohydrate is provided to players.

Overall, I believe this is a very good, interesting, relevant and well organized study. However, I do think a few things should be pointed out as limitations of this study. Soccer is the biggest sport worldwide, played in more than 200 countries in all continents and in my opinion the results of only 17 players cannot reflect the truth for all of them. So it would be better if this study could be done on a larger number of athletes and in different regions or even countries if possible. Another point is that for this study, the athletes were in a glycogen-reduced state before beginning the test, which is far from reality in a competitive match. Finally, for this test, the athletes were provided a drink solution every 15 minutes, which would be very hard to occur during a soccer match.

Based on these findings we could suggest the ingestion of carbohydrate-electrolyte solutions before and during the game, although the only real option during the game would be half time (other chances to stop and drink during the match are very rare). Even though there was no statistical difference in terms of skill performance in between the two groups, the presence of carbohydrate solution appeared to induce metabolic and perceptual benefits compared to when no carbohydrate is provided to the athletes. For all competitive sports, including soccer, every small improvement in performance is welcome.

Unanswered questions:

- Would these results be different for athletes in a high glycogen state?

- Would a solution containing both carbohydrate and protein change the results?

- How was the energy expenditure not different between trials if carbohydrate oxidation was significantly higher in the carbohydrate trial, whereas fat oxidation was significantly higher in the placebo trial?

Attachment: File

Soccer Nutrition.pdf (427.991 KB)

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Thread:: Eating Disorders in Collegiate Athletes
Post:: Eating Disorders in Collegiate Athletes
Author:: Vickie Machen

Posted Date:: September 12, 2012 9:55 AM
Status:: Published

Research Review 1

(A). Johnson, C., Crosby, R., Engel, S., Mitchell, J., Powers, P., Wittrock,

        D., Wonderlich, S. (2004). Gender, ethnicity, self-esteem and

        disordered eating among college athletes. Eating Behaviors,

        5, 147-156. Retrieved from http://www.sciencedirect.com/science

        /article/pii/S1471015304000091.

(B). The purpose of this study is to provide evidence of the ethnic and gender differences like self-esteem and the eating disorder attitudes and behaviors among collegiate athletes. Women report lower self-esteem and higher body dissatisfaction than men and black women. Protective factors against eating disorders like body dissatisfaction, drive for thinness, and low self-esteem were undertaken on a large sample of NCAA Division I athletes for the comparison of ethnic and gender differences.

(c). For the methods portion, there are a total of 1445 collegiate athletes that participated among which 562 were female and 883 male. These athletes were from 11 schools in 11 different sports and were classified in the high-risk sports for eating disorders. Materials used were a student-athlete questionnaire that has 133-item self-report measure designed to collect information from demographics, eating-related behaviors, drug and alcohol intake and the attitudes concerning body image and weight-related issues.

Results indicate that females demonstrated lower self-esteem than males, significant main effect for ethnicity was found and black participants demonstrated higher self-esteem than white. Lastly, a significant two-way Gender X Ethnicity interaction was found where white females had lower self-esteem than black females and both groups of men. All of the same factors were true for body dissatisfaction as well.

(D). This research study’s results are somewhat disturbing, considering white female athletes reported significantly lower self-esteem and significantly higher rates of disturbed eating attitudes and behaviors than Black females, Black male, and White male athletes. White women tend to have highly conditioned bodies and experience athletic success which one would hope that having this success in athletics would be a protective factor against low self-esteem, body dissatisfaction, and eating disorder behaviors. However with this study it was shown that this is not the case. Even more bizarre is how the Black female athlete’s factors closely resembled their male counterparts; in fact, the self-esteem scores were almost identical to both Black and White males.

(E). This study is very simplistic and easy to follow and the terminology makes it more comprehendible for review. There were several different variables but they were defined and analyzed in a matter that anyone could understand. Plus this study was organized so one could depict the variable that most satisfies the type of athlete they train to ensure proactive measures can be taken to eliminate the possibilities of low self-esteem, high body dissatisfaction, and the eating disorder problems.

(F). Practical application of this study would be to utilize the results so when I am training my athletes I can look more closely at the white females for the possibilities of acquiring; an eating disorder, low self-esteem, and high body dissatisfaction. I would not only focus on the white females but also by sport, the distance runners and swimmers would be close on my radar to ensure as a strength coach they do not acquire any of the negative implications of sport specific training.

Unanswered Questions:

1. Since white females are the dominant to attain low self-esteem and high body dissatisfaction what measures can be taken to ensure that an eating disorder will not occur?

2. If the black females are equal to both the white and black males in the self perception, is there a possibility that black women could potentially revert to the ways of the white females?

3. If the sport requires low weight or body fat percentages, how do we prevent negative weight loss as opposed to reacting after the bad habit has already occurred?

Attachment: File

Research Review 1.docx (16.84 KB)

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Thread:: Review #1
Post:: Review #1
Author:: Lauren Massie

Posted Date:: September 10, 2013 11:32 PM
Status:: Published

Attachment: File

research review 1.docx (16.233 KB)

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Thread:: Research review
Post:: Research review
Author:: Woncheol Noh

Posted Date:: September 23, 2013 12:25 AM
Status:: Published

Attachment: File

Research review 1.doc (31.5 KB)

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Thread:: Development of hydration strategies to optimize performance for athletes in high intensity sports and in sports with repeated intense efforts
Post:: Development of hydration strategies to optimize performance for athletes in high intensity sports and in sports with repeated intense efforts
Author:: Teodoro Olivarez

Posted Date:: September 22, 2013 11:56 PM
Status:: Published

Research Review #1

Source

Maughan, R. J., & Shirreffs, S. M. (2010). Development of hydration strategies to optimize performance for athletes in high-intesity sports and in sports with repaired intense efforts. Scandinavian Journal of Medicine & Science in Sports, 20(2), 59-69. Retrieved fromhttp://ehis.ebscohost.com.manowar.tamucc.edu/eds/pdfviewer/pdfviewer?sid=5cff6d6d-7dd0-4aa6-affe-6c3bc184ff03@sessionmgr15&vid=5&hid=16

Purpose of Study

The purpose of this study was to determine the importance of hydration in regards to maintaining a high level of performance during high-intensity sports as well sports with repeated intense efforts such as football, basketball, etc.

Methods and Materials

In order to determine the effects of proper hydration what first needed to be done was to have a starting point or factor. Each athlete that was to determine a pre-hydration status in order to evaluate the effects during the workout and at the end of the workout. This was measured by urine markers such as osmolality, conductivity, and urine color. Also in certain cases, and in terms of resources, changes in plasma osmolality can track progressive changes very well throughout the body. Depending on resources this would be a great way to track progressive changes in body mass during exercise, but there are certain variables that could effect this particular study. Another method of studying is by sweat analysis and water loss during the high intensity sports. Determining the loss of electrolytes by utilizing the whole body wash down technique will provide the most accurate results, but in terms of resources application of an absorbent swab to an area that is clean and dry would provide the necessary results to evaluate.

Summary of Results/Conclusions

There is no denying that dehydration can have a massive effect on both physical and mental performance hindering the individual from performing at their best. Which is why it is vital to incorporate fluid replacement strategies when large amount of sweat losses occur. Each individual athlete is different, therefore, each person requires a different strategy for hydration. It would be vital for the athlete to identify their own needs for hydration to better improve performance.

Critique of the Study

The study is an interesting one in regards to hydration and the importance of it. Being able to analyze different aspects of the human body to determine proper strategies to rehydrate at the right time. Although it provides a detailed description of the different tests and methods there are some areas that leave a cause for concern. The concern would be the variables that could affect the study such as how each individual hydrates after a urine sample was collected which in turn could alter the results or how obtaining the sweat analysis could alter the results as well.

Practical Application of the Study

Each athlete and individual, in regards to training, or in everyday life has their own unique way of how their body sweats and how their metabolism works. No one person will need to hydrate the same way as another because each body is different. So determining what strategy works for hydration will greatly improve their overall performance. Staying hydrated is key to maximizing athletic performance and minimizing injury.

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Thread:: Nutrient timing revisited: is there a post-exercise anabolic window
Post:: Nutrient timing revisited: is there a post-exercise anabolic window
Author:: Gregory Peckels

Posted Date:: September 22, 2013 9:59 AM
Status:: Published

Greg Peckels

KINE 306

21 SEPTEMBER 2013

Title

Nutrient timing revisited: is there a post-exercise anabolic window.

Purpose of Study

The purpose of this research study was to perform a systematic review of previous literature on the effects of nutrient timing following exercise, while exploring muscular adaptations to specified nutrients consumed, and also to describe nutritional recommendations based on evidence-based research to help optimize the anabolic response to exercise. The article examines glycogen repletion, protein breakdown, protein synthesis, and muscle hypertrophy in respect to specific training protocols and gives recommendations on specific nutritional intake with respect to anabolism.

Methods and Materials

Multiple studies have been investigated to determine whether an anabolic window exists in the immediate post-exercise state and what recommendations are relevant to obtain optimal nutritional supplementation to maximize the body’s anabolic response to exercise. All research that is referenced in the current article was determined via systematic review. It is widely known that during intense physical activity, muscle glycogen stores and amino acids are depleted, protein breakdown occurs, all causing damage to muscle fibers, requiring some sort of nutritional intervention. An example from previous research is that glycogen repletion is considered essential to optimal resistance training performance, with as much as 80% of ATP production during such training derived from glycolysis. There is evidence that adding protein to a post-workout carbohydrate meal within a two hour time period can enhance glycogen re-synthesis. It has also been determined that protein breakdown can also be avoided by post-workout supplementation. Previous research has shown this to be true by trying to spike insulin levels, helping to regain adequate protein levels in the body. It is also added that the majority of support for post-exercise supplementation has been conducted while the subject have been in a semi-fasting state.

Summary of Results/Conclusion

Previous research has indicated that immediate post-exercise intake is essential to maximize hypertrophic gains, supporting an “anabolic window of opportunity.” According to this systematic review, the “anabolic window of opportunity” is far from definitive. Considering the majority of previous research that has been conducted is considered to be in the fasted exercise category, a simultaneous increase in muscle protein breakdown causes the pre-exercise net negative amino acid balance to persist in the post-exercise period despite training-induced increases in muscle protein synthesis. If performing resistance training following an overnight fast, it is ideal to consume a combination of protein and carbohydrate to promote muscle protein synthesis. This will reduce proteolysis, switching a net catabolic state into an anabolic one. If done continuously, this tactic of getting adequate protein and carbohydrate prior to training could, conceivably, lead to an increase rate of gains in muscle mass. Immediate protein-rich meals post-exercise, as once recommended seem redundant and can be consumed up to two hours to maximize recovery and anabolism, if consuming a combination of protein and carbohydrates prior to exercise. It is also not definitive for those wanting to optimize a hypertrophic response of the potential of post-exercise supplementation. More research needs to be conducted to examine pre- and post-exercise supplementations against each other. According to this review, this prevents the possibility of isolating the effects of either pre- or post-exercise supplementation.

Critique of the Study

I found this systematic review very informative and can relate the majority of their findings to my current profession. I am an athletic trainer working with high level athletes and nutrition plays a large roll in maximizing athletic performance. Even though more research needs to be conducted to look at specific factors, overall high intensity exercise bouts should include some form of pre- and post-exercise consumption of protein and carbohydrates to maximize hypertrophy and the anabolic response to exercise. This review details specifically how long pre- and post-exercise this should occur, and how much per kilogram of body weight should be ingested.

Practical Application(s) of the Study

The practical application of this study that should be noted is the consumption of a high-quality protein (dosed at 0.4-0.5 g/kg of lean body mass), both at pre- and post-exercise to maximize the anabolic response, resulting in a muscle hypertrophy state, which is a goal of the majority of athletes. These relatively high protein dosages should not be separated by more than 3-4 hours (pre- and post-exercise of which that lasts 60-90 minutes) to maximize the results of hypertrophy. The timing of carbohydrate dosage and timing relative to resistance training lacks statistical data to give recommendations for the role that carbohydrates play in muscle hypertrophy. However, if exercising in a state of fasting, it is recommended that protein and carbohydrate supplementation is to be ingested with relative urgency to help reduce the breakdown of protein and restore the body to more of a catabolic state.

Unanswered Questions

What is the optimal carbohydrate/protein (liquid/solid food) to consume pre- and post-exercise?
The recommendations given are directed to more of an anaerobic weightlifter. Does the carbohydrate and protein consumption, g/kg lean body mass, change if you are looking for more of an aerobic result (cross country runner, cycling), such as muscular endurance?
Considering the results are based on pre-exercise fasting (waking up after sleeping and engaging in 60-90 minutes of moderate-intense exercise), would the results differ if these studies had occurred mid-day, after breakfast and lunch were consumed?

Reference

Aragon, A., & Schoenfeld, B. (2013). Nutrient timing revisited: is there a post-exercise anabolic window. Journal of the International Society of Sports Nutrition, 10(1), 5.

Attachment: File

Nutrient Timing Revisited Article.pdf (199.785 KB)

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Thread:: The differential effects of a complex protein drink versus isocaloric carbohydrate drink on performance indices following high-intensity resistance training: a two arm crossover design
Post:: The differential effects of a complex protein drink versus isocaloric carbohydrate drink on performance indices following high-intensity resistance training: a two arm crossover design
Author:: Byron Pottorff

Posted Date:: September 22, 2013 11:44 PM
Status:: Published

The differential effects of a complex protein drink versus isocaloric carbohydrate drink on performance indices following high-intensity resistance training: a two arm crossover design

Source:

Lynch, S. (2013). The differential effects of a complex protein drink versus isocaloric carbohydrate drink on performance indices following high-intensity resistance training: a two arm crossover design. Journal of the International Society of Sports Nutrition. (10-31).

Purpose:

The purpose of the study is to investigate the effects of a protein based drink versus an isocaloric carbohydrate drink post high-intensity workout.

Methods and Materials:

The study used 15 males, ages 25-38 from the same fitness club in Burbank, CA. Each had to meet the same criterion of working out at least an hour, five times a week for the past year. All volunteers with previous musculoskeletal issues were excluded from the study. The chosen subjects were then put through a double blind cross arm test where they would be given one of the two drinks after the high intensity workout and then brought back for testing two hours later. A week later they would go through the same process and would be given the other drink.

The high-intensity resistance training (HIRT) was a 15-18 minute circuit workout at a ratio of two minutes of work to one minute of rest that would be preceded by a 10 minute standard dynamic warmup. The HIRT included eight reps of each; overhead dumbbell push press, squats with dumbbells, dumbbell push-ups and repeated for the “work” duration. This would be repeated for five to six sets.

Roughly five minutes following the resistance training session the subjects would be given one of the two drinks. The first being the VPX Protein Rush Chocolate Dream as the complex protein option and the other simply orange flavored Gatorade as the isocaloric carbohydrate drink.

After a two hour fast period the subjects would return to be tested on to try to determine the rate of perceived exertion. They were put through an agility t-test, a push-up test (to exhaustion) and a 40-yard dash speed test. A week later the process would be repeated and but assessed against the other drink option.

Summary of Results:

A repeated measures analysis of variance was used to to detect if there were any effects of the dependent variables of time between each trial and between the trials and introduction of treatment. It turned up insignificant in relation to the trials and the independent drinks. A repeated measure multi-variance analysis of variance was also done. This was done to evaluate the effects of the treatment on the results of the agility, speed and strength testing. The results turned up significant (p<0.01) which means the belief that there was no difference between the drinks is incorrect.

In conclusion this study shows that there were better test results with the VPX protein complex than with the Gatorade representing the carbohydrate based drink in the study. This means that the VPX complex helped with recovery and muscle protein synthesis post workout.

Critique of Study:

I found this to be a particularly interesting topic as it is one that is often debated and studied in the sports performance world. I especially thought that the design of the experiment in that it tested the same people with both drinks yet it was still a double blind format. It seems Gatorade had always advertised itself as the gold standard for recovery until recent years. Then as more and more studies are showing the importance of protein for recovery the tides are really changing, Gatorade has even released its own protein based recover drink. It’s very important that we continue to see what works best for our bodies to perform as a human population and even between different sects on an individualized basis.

Practical Application:

The real life application of this is simply just suggesting that athletes I deal with as an athletic trainer to use a protein based drink for recovery although an isocaloric carbohydrate drink can we useful we are finding that they are more appropriately used in replacing electrolytes.

http://www.jissn.com/content/pdf/1550-2783-10-31.pdf

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Thread:: Contextual Body Image and Athletes' Disordered Eating:
Post:: Contextual Body Image and Athletes' Disordered Eating:
Author:: Susan Proctor

Posted Date:: September 22, 2013 6:17 PM
Status:: Published

Susan Proctor

Research Review 1

KINE 5306 – (Advanced Nutrition)

Contextual Body Image and Athletes Disordered Eating: The Contribution of Athletic Body Image to Disordered Eating in High Performance Women Athletes

Reference

De Bruin, A., Oudejeans, R.D., Bakker, F.C., & Woertman, L. (2011). Contextual body image and athletes’ disordered eating: The contribution of athletic body image to disordered eating in high performance women athletes. European Eating Disorders Review, 19(3), 201-215.

Purpose of Study

The purpose of the study was to investigate the contribution of a contextual body image perspective to understanding disordered eating in high performance women athletes.

Methods and Materials

Two separate studies were preformed, in study 1 a questionnaire was developed to measure multidimensional body image in daily life and sport. Heterogeneous samples of female sports participants and exercisers were given the questionnaire. In study 2 they examined the athletes and filled out the questionnaire from sports in which leanness, low weight, or appearance are considered to be of great importance.

Summary of Results and Conclusion

Study 1 the factor analysis of the 15 life body images items revealed the presence of four components with values exceeding 1, explaining 79.4% of the total variance. The analysis of athletic body image revealed the presence of three components explaining 76.7% of the total variance. Four identical factors were distinguished in both contexts allowing a good comparison between body evaluation and in daily life and sport. (1) Appearance (2) muscularity (3) self-evaluations of shape/weight/fat (4) perceived opinions of others on shape/weight/fat.

Study 2 produced results using four identical scales for daily life and sport constructed in order to be able to compare the athletes’ body evaluations in those contexts. There was a sample of 52 women athletes, and the internal consistency of the scales ranging from .79 to .93.

Critique of the Study

The study was very well organized and used the appropriate measures and scales to make their comparisons and test their hypothesis. They used different methods and different ways to measure the subjects, giving the study a little more validity because they took the time to do it more ways than one, allowing for different points of view.

Practical Application of the Study

Most female athletes are very self-conscious of their body image and sometimes do not do what is nutritionally good for them. I believe this study will assist female athletes in choosing the right nutritional plan as they plan to compete and it will be a tool for them to evaluate if what they are doing benefits them in every possible way.

Questions

What would be another way to test a study like this?

Attachment: File

60622074.pdf (154.791 KB)

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Thread:: Weight maintenance, behaviors and barriers among previous participants of a university-based weight control program
Post:: Weight maintenance, behaviors and barriers among previous participants of a university-based weight control program
Author:: Katherine Spotswood

Posted Date:: September 19, 2013 10:44 AM
Status:: Published

Katherine Spotswood

Research Review 1

Title of Article:

Weight maintenance, behaviors and barriers among previous participants of a university-based weight control program

Purpose of Study:

The purpose of this study was to compare behavioral strategies and perceived barriers between successful and unsuccessful weight management programs. The article examines weight loss maintenance among previous participants of a university-based weight management program. This research was conducted to study the overwhelming evidence that most individuals experience significant weight regain during the first year following a weight loss program, and almost all experience complete regain within 5 years of the program.

Methods and Materials:

The research was conducted at the University of Kansas Medical Center, using The Weight Control Research Project (WCRP), which is a university-based clinic incorporating structured diets and behavioral weight management with weekly group meetings. Respondents to this study participated in the clinic between 2000 and 2004 in one of four extents examining various dietary factors influencing weight loss and weight loss maintenance. Eligible participants had a BMI between 28 and 40, and were deemed medically stable with clearance from a physician. In the original study, participants that completed treatment to at least the three month weight loss phase was (n=417), and to which to data from this current study was taken. For the current study, 170 previous participants from the above mentioned study completed mailed surveys in 2008 assessing current weight, weight control behaviors, and perceived barriers to weight loss maintenance.

Summary of Results and Conclusion:

The results of this study yielded that respondents were on average 11-10% below baseline weight, and 76.5% of respondents has successfully maintained weight. In accounting for time since treatment, the strongest correlates of successful weight loss maintenance were frequent exercise and perceived difficulty of weight management. The findings support that physical activity is one of the strongest predictors of successful weight loss maintenance. As for weight control behaviors across successful and unsuccessful maintainers, the most commonly reported barriers to weight loss maintenance were ease of slipping back into old habits, job commitments, family commitments, and lack of time for exercise.

Critique of the Study:

This study was interesting in that it is not a test, re-test study, but more of a follow-up type of study. The original study done in 2000-2004 was a very strict diet and exercise regime of over 600 people. The original study regulated the amount of caloric intake and expenditure of each person who participated in the study. It provided participants with carefully balanced daily nutritional meals, daily exercise routines, and mandatory weekly lecture/meetings that served also as a support group for the participants. The participants were not required or even informed about a follow up study, but the researchers thought it would be beneficial to learn if the techniques embedded in the participants of the study over four years ago were still holding up and being utilized. As the research showed, that participants did generally experience weight maintenance, however there is much concern to the validity of claim to this research. One reason is that well over half of the participants of the original study did not participate in the follow up, and thus, were not represented in its findings. Another reason is that a mailed survey holds a tremendous margin of error. It is too easy to fill in the “right” or preferred choice/answer on a survey, and if the researchers wanted to be truly accurate then they would have had the participants come back in so that they could re-evaluate their BMI and its amount of change since the study’s conclusion four years ago. Another controlled experiment would have been the best measure of validity, where there is no glamorization of self, only true physiological evidence.

Practical Application of the Study:

This study is applicable to the fact that weight-loss, as in many cases, is fleeting, and as previous studies show, most individuals experience significant weight regain during the first year following a weight loss program, and almost all experience complete regain within 5 years. However, this study suggests that weight loss maintenance is possible when associated with consistent behavioral patterns.

Reference:

Befort, C. A., Stewart, E. E., Smith, B. K., Gibson, C. A., Sullivan, D. K., & Donnelly, J. E. (2008). Weight maintenance, behaviors and barriers among previous participants of a university-based weight control program. International Journal Of Obesity, 32(3), 519-526. doi:10.1038/sj.ijo.0803769

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Thread:: Effect of milk-based carbohydrate-protein supplement timing on the attenuation of exercise-induced muscle damage.
Post:: Effect of milk-based carbohydrate-protein supplement timing on the attenuation of exercise-induced muscle damage.
Author:: Michael Terencio

Posted Date:: September 22, 2013 2:16 AM
Status:: Published

Michael Terencio

KINE 5306 – Advanced Nutrition

Dr. Kelly Brooks

Sunday, September 22, 2013

Research Review 1:

Cockburn, E., Stevenson, E., Hayes, P.R., Robson-Ansley, P., and Howatson, G. (2010). Effect of milk-based carbohydrate-protein supplement timing on the attenuation of exercise-induced muscle damage.

Applied Physiology, Nutrition, and Metabolism, 35, 270-277.

Purpose of this Study

The aim of this investigation was to examine whether consuming milk-based carbohydrate-protein

(CHO-P) before muscle-damaging exercise is more beneficial in attenuating exercise induced muscle damage

(EIMD) than consuming it immediately (within 30 minutes) and/or 24 hours later.

Methods and Materials

Thirty-two healthy males ranging from 18 to 22 years of age participated. All participants regularly competed in sports, but never on the collegiate or professional level. All individuals maintained their habitual diets. After ethical approval, all procedures, benefits, and associated risks were explained, then all participants gave their written informed consent.

For procedural design, participants were assigned to 1 of 4 groups and all were equally matched based on concentric knee flexion peak torque recorded from 6 knee extension-flexions during preliminary testing via Cybex isokinetic dynamometer. The four groups were allocated as follows: one group consumed CHO-P before EIMD (PRE), one group consumed CHO-P immediately after EIMD (POST), one group consumed CHO-P 24 hours after EIMD (TWENTY-FOUR), and the last group consumed water but no CHO-P supplementation (CON). A 1-way analysis of variance (ANOVA) was utilized to show no significant differences in age, height, and body mass among all participants and no significant differences in the peak torque values used for group allocation.

The CHO-P nutritional supplement was a shake called For Goodness Shakes made by My Goodness Ltd. in London, UK. Each shake was 1000 mL which consisted of 707 calories, 33.4g of protein (made of a casein and whey mix), 118.2g carbohydrates (CHO), and 16.4g fat. Each participant within each group took 1000 mL because previous studies had shown significant attenuation of decreases in isokinetic muscle performance and increases in creatine-kinase (CK) with this portioning procedure.

Exercises were performed in the hamstrings utilizing unilateral knee flexions. The right leg performed 6 sets of 10 reps, with 90-second rest intervals, then the left leg followed suit. The degree of active DOMS experienced by participants was measured with a visual analogue scale which ranged from zero (no pain) to ten (as bad as it could be). Muscle performance was measured through peak torque and reactive strength. Peak torque measurements were examined with a Cybex isokinetic dynamometer. Participants performed six reps with maximal extension, flexion, and range of motion. Reactive strength measurements were examined via an AMTI force plate. Each participant performed 3 separate drop jumps from a 43cm tall box, and the mean of the 3 jumps was recorded and utilized. Each individual dropped from the box and upon landing, jumped for max height with minimum contact time. Reactive strength index (RSI) was calculated by dividing jump height in centimeters by contact time in seconds (RSI = jump height/time). A fast RSI reading indicated an increased utilization of the stretch-shortening cycle. The hamstring was not isolated, but the RSI calculation gave a global picture of performance for several types of athletes.

Blood sample collection and analysis utilized a serum CK concentration collected via venipuncture from the forearm vein, then centrifuged. Thirty mL of the resulting serum was used for immediate CK analysis.

Statistical data analysis was based off magnitude-based inferences because this method defines the smallest biological effects and focuses on absolute effect instead of noneffect interpretation.

Summary of Results/Conclusion

All DOMS activity peaked at 48 hours after EIMD and began to return to baseline at 72 hours. From baseline to 48 hours, POST group showed greater reduction in soreness over the CON and PRE groups. From baseline to 72 hours, the PRE group showed beneficial recovery over the CON and TWENTY-FOUR groups.

Muscle performance benefits showed limiting decreases in peak torque and RSI. From baseline to 48 hours, the POST and TWENTY-FOUR groups showed the highest benefits and from baseline to 72 hours the PRE and POST groups showed the most benefits.

CK benefits were measured by increases of CK after exercise. From baseline to 48 hours, the POST and TWENTY-FOUR groups showed the highest increases. From baseline to 72 hours, the POST and PRE groups showed highest increases.

In conclusion, consuming CHO-P at any time increases CK activity. Supplementing CHO-P attenuates EIMD by increasing protein synthesis and limiting degradation. Consuming CHO-P before exercise decreases active DOMS and increases peak torque over 72 hours. Consuming CHO-P immediately after exercise decreases active DOMS and increases performance over 48 hours. For an athlete, consuming a carbohydrate-protein mixed shake immediately after exercise seems to be the most beneficial for athletes because they tend to train more frequently than every 3 days.

Critique of the Study

A placebo with equicaloric content was not considered, so benefits of CHO-P due to additional calories may want to be matched in later investigations. All the results seemed unbiased and came from the quantitative data of the study and other concurrent studies. All findings throughout the investigation were supported with evidence. The authors’ discussion was fully supported with data. Overall, I look forward to learning from more studies like this one.

Practical Applications of the Study

As a personal trainer, I can see myself using this information as a referral guideline for clients. Also, this information can be deemed very useful for a wide array of professionals including exercise physiologists, exercise rehabilitation specialists, public health and health care professionals, as well as basic and applied physiologists, biochemists, and of course, dieticians.

Attachment: File

Wk. 2...ResRev 1.docx (20.443 KB)

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Thread:: Weight Loss and Exercise Training Effect on Oxygen Uptake and Heart Rate Response to Locomotion
Post:: Weight Loss and Exercise Training Effect on Oxygen Uptake and Heart Rate Response to Locomotion
Author:: Alejandro Trejo

Posted Date:: September 21, 2013 1:18 PM
Status:: Published

Alejandro M Trejo

09/21/13

RR#1

Source

Hunter, G. R., Fisher, G., Bryan, D. R., & Zuckerman, P. A. (2012). Weight loss and exercise

training effect on oxygen uptake and heart rate response to locomotion. The Journal of

Strength and Conditioning Research, 26(5), 1366-1373.

Purpose

The purpose of this study was to study the effects of resistance and aerobic training on the simplicity of physical activity during and after diet-induced weight loss. The hypothesis was both aerobic and resistance training during diet-induced weight loss will decrease heart rate while walking, stair climbing, and biking more than just dieting only. The researchers also hypothesized both aerobic and resistance training will sustain reduced heart rates while walking, stair climbing, and biking during the year after weight loss versus the subjects who didn’t include exercise will experience an increase in heart rate while walking, stair climbing, and biking. The values of strength, aerobic fitness, HR, respiratory quotient (RQ), and VO2 during submaximal steady-state cycle ergometry, stair climbing, treadmill, and a 2.5% grade treadmill walk from the study. The variables were measured three different times during the study. The first measurement was taken at baseline variables before diet and training began, the second time was after an 800 kcal·diet-induced diet with or without exercise designed to reduce body mass index to less than 25 kg· and after one year of the achievement of 25 kg·. The variables seem to be an accurate measure when comparing activities of everyday living.

Methods and Materials

The study involved 73 overweight pre-menopausal women who were randomly assigned to one of three groups which were diet and aerobic training, diet and resistance training, and diet and no exercise training. The subjects were assigned to train three times a week during dieting phase and two times a week the following year after. The subject’s weights were stable for month before all the evaluations. Researchers had the subjects do three weekly weight measurements and adjusted for energy intake when needed. Diet macronutrient content consisted of 20-22% fat, 20-22% protein, and 56-58% carbohydrates. Two days before all evaluations, the subjects were admitted into the General Clinical Research Center to measure physical activity and their diets. Testing was administered while subjects were in a fasted state. Training for the aerobic group consisted of a five minute warm-up of stretching or walking on a treadmill. During the first week of training, the subjects performed 20 minutes of exercise at 67% maximum heart rate. Both intensity and duration increased each week so that by the eighth week the subjects could perform 40 minutes of exercise at 80% max heart rate. Training for the resistance group consisted of a treadmill warm-up for five minutes and five minutes of stretching. Resistance training included squats, leg press, elbow flexion, lateral pull-down, bench press, triceps extension, military press, leg curl, knee extension, lower back extension, and bent leg sit-ups. One week of accommodation with the exercises at light weight was completed before 1RM testing was examined. The first week of weight training started at 65% of 1RM for ten repetitions. Percentage of 1RM was increased every week until goal of 80% was reached by week eight. At week 4 subjects performed two sets of ten repetitions with a two minute rest in between sets. Strength was assessed every five weeks and weights were adjusted accordingly. The Bruce protocol was used to measure VO2 max. Heart Rate, Respiratory Quotient, and VO2 were measured during submaximal steady-state ergometry at 50 watts, stair-climbing at 60 steps per minute, treadmill walk neutral at 4.8 km/hr, and a 2.5% grade treadmill walk at 4.8 km/hr.

Descriptives were analyzed using a 1-way (group) analysis of variance. A 3 (group) by 3 (time) repeated measured analysis of variance was used to examine all variables. The researchers also used a T-Test Bonferroni corrected post hoc tests were run to compare the pooled exercise subjects against the no exercise control group. The significance was set at p≤ 0.05.

Summary of Results/Conclusion

The post hoc analysis showed the strength group improved on strength when compared to the other groups and that the aerobic group increased VO2max when compared to the other groups. Post hoc tests also showed that the subjects who exercised significantly decreased their heart rates in all the tasks that were measured more when compared to the non-exercise group between the initial baseline measurement and the 1-year follow-up measurement. The post hoc discovered that there was no differences in decreased heart rate between those who exercised and those who didn’t exercise for 3 out of the 4 steady-state ergometry tests between baseline and post-weight loss. Quadratic time by group interactions were significant for the sub-maximal walk (p<0.02) and grade walk (p<0.02), although post hoc tests showed significant decrease in respiratory quotient between baseline and post-weight loss state for aerobic group in sub-maximal walk and grade-walk.

The results addressed the hypothesis on how aerobic and resistance training coupled with diet can and do effect the ease of physical activity. The results also addressed this hypothesis by comparing results between the two training groups and explained on how they either increased or decreased between the baseline measurements and post-weight loss measurements. The researchers also examined the physiological influences that either did or did not accompany the changes in heart rate, respiratory quotient, and VO2max. The researchers displayed their results and their implications and made some suggestions for practical application. They discussed the importance of the results and what that means towards the measurements. The reserchers concluded that the heart rate for the aerobic group decreased for the walking, stair-climbing, and grade walking. Heart rate decreased minimally in the resistance trained group on the same tests. The researchers also came to the conclusion that both aerobic and the resistance trained groups maintained their respective heart rates at the end of the year after post-test. The estimated that this decreased heart rate transfers over to increased physical activity and to reduced weight gains. Overall, the aerobic and resistance training groups were the only ones who decreased their hear rates during sub-maximal tasks but the mechanisms for improvement were different. The researchers suggest that improvements in aerobic fitness were accompanied by increases in blood volume and increases in sub-maximal and maximal stroke volume. Increased stroke volume would have explained to lower resting heart rate during submaximal exercise. The resistance training had little to no effect on aerobic capacity and maximal stroke volume.

Critique of Study

Overall, the study proved that the hypothesis was indeed correct and provided good information on the effects of a diet on exercise and the body. The researchers needed to include more in-depth nutritional facts about the diet because the percentage of fats, carbohydrates, and protein may have had a huge impact on the training and the outcome. It would also better if there was a group that combined both aerobic and resistance training because the combination of the two would have had likely had additional effects and results on the study.

Practical Applications

Diet-induced weight loss coupled with exercise had an impact on heart rate and walking, stair climbing, and bicycling. This affected both aerobic and strength fitness as well as overall health and every day activities. Even though the post weight loss heart rate did not change the benefits of continuing to exercise can maintain the heart rate to be low and also maintain weight loss. Moderate intense exercise and diet can help ease daily life and improve physical appearance and as well as overall health.

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Thread:: The Role of Canteen Shape in Troop Hydration
Post:: The Role of Canteen Shape in Troop Hydration
Author:: Elizabeth Trevino

Posted Date:: September 22, 2013 10:40 PM
Status:: Published

Elizabeth Trevino

KINE 5306

The Role of Canteen Shape in Troop Hydration

Wansink, B., Cardello, A., & North, J. (2005). Fluid consumption and the potential role of canteen shape in minimizing dehydration. Military Medicine, 170, 871-873.

Dehydration is serious concern for athletes and military personnel alike. By the time an athlete starts to ‘feel’ thirsty, he/she is already at stage four in the stages of dehydration paradigm. Efforts to increase fluid consumption focus on maximizing the availability of fluids. One way this is implemented, especially within the armed forces, is by assigning personal water canteens to each soldier. Although the military issues a standard canteen of one quart in volume, athletes have access to all shapes and sizes of personal water bottle containers. The purpose of this study is to determine whether or not canteen dimensions play a significant role in the biases of ROTC cadets as to how much fluid they poured and subsequently consumed.

50 Army and Marine ROTC students from the University of Illinois at Urbana-Champaign participated in this experiment. In an effort to keep the results as accurate as possible, 50 University of Illinois at Urbana-Champaign students were brought in to participate alongside the ROTC cadets. The results of the students were not analyzed with the cadets’ data – the use of students was so the cadets wouldn’t feel singled out because of their cadet status. IRB consent was not explicitly stated in the article. Water consumption was assessed one hour after routine training. The cadets were allowed water immediately following exercise, but not presented any water until the administering of the experiment. Two shapes of clear plastic water bottles were distributed to the cadets. One was more cylindrical and tall while the other was shorter and more round around the middle; both were 32 ounces. The cadets were asked to fill their water bottles and report how much fluid they thought they had poured.

The cadets that had been given the shorter, rounder of the water bottles poured 38% more water than those with the taller water bottles did. Both groups of cadets drank all of the water that they had poured for themselves. The study shows us that the elongation of a water bottle negatively influences pouring volume; ROTC cadets consumed more water when they poured into short, wide water bottles. Essentially what the results tell us is that we are visual with our food and water consumption. Even though both bottle sizes were 32 ounces in volume, elongation positively influences perceived volume. During the hot, humid summer months, bottle size could potentially have an effect on the hydration status of an athlete simply because of the perceived water consumed by said athlete.

The current experimental design tests the water consumption and perceived consumption one hour after physical activity in a controlled setting. A critique of the study would be that there needs to be real world application. Repeating the experiment on the sports field may yield completely different results. Also, varying subjects are needed to help substantiate the claim of bottle size and perceived water consumption.

It has become common practice as of late for long distance running coaches to require their athletes to carry around a gallon jug full of water and have them drink the entirety of the contents before the school day ends. While the mindset behind the practice is to ensure that endurance athletes stay hydrated, there really is no magic recommendation as to how many ounces of water per day an athlete needs to consume in order to stay adequately hydrated. I can remember being required to drink a whole gallon of water and hating the task because of the daunting size of one gallon of water. If there is truth to the above research article, it might serve as a better means of staying hydrated throughout the day. I carry around a Nalgene at work and end up refilling it 2-3 times in an 8hr work day and it doesn’t even phase me as to how much water I consumed. I’m positive, however, that I would more than likely not finish a one gallon jug in the same work day.

https://manowar.tamucc.edu/login?url=http://search.ebscohost.com/login.aspx?direct=true&db=a9h&AN=18713262&site=eds-live&scope=site

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Thread:: Effects of a carbohydrate-, protein-, and ribose- containing repletion drink during 8 weeks of endurance training on aerobic capacity, endurance training, and body composition
Post:: Effects of a carbohydrate-, protein-, and ribose- containing repletion drink during 8 weeks of endurance training on aerobic capacity, endurance training, and body composition
Author:: Brian Warren

Posted Date:: September 22, 2013 8:38 PM
Status:: Published

Brian Warren

KINE 5306

September 22, 2013

Research Review #1

Source

Cramer, J., Housch, T., Johnson, G., Coburn, J., Stout, J. (2012). Effects of a carbohydrate-, protein-, and ribose- containing repletion drink during 8 weeks of endurance training on aerobic capacity, endurance training, and body composition. The Journal of Strength and Conditioning Research. 26 (8), 2234-2242.

Purpose of Study

The purpose of this study was to test the effects of a repletion drink which contained a combination of CHO, protein and ribose on aerobic capacity, endurance performance and body composition during 8 weeks of endurance training.

Methods and Materials

Thirty two men (age, mean ± SD =23 ± 3 years) performed tests for aerobic capacity (VO₂peak), time to exhaustion (TTE), at 90% VO₂peak, and percent body fat (%fat) and fat-free mass (FFM). This was a randomized, double-blinded parallel study. All subjects participated in an exercise training program consisting of 1-hour cycle ergometry exercise performed 5 times per week, for 8 weeks. Additionally, each subject underwent testing at 4 time intervals (pre-training [PRE], mid-training at 3 weeks [MID3], mid-training at 6 weeks [MID6] and post-training [POST]). All 4 tests, PRE, MID3, MID6, and POST consisted of body composition assessment, an aerobic capacity test, and a fixed power output endurance test. Each laboratory visit was performed approximately at the same time of the day (± 2 hours). The subjects were randomly assigned to either the treatment drink (TEST; n=15) or the control (CON; n=17). The CON drink was designed to have the same caloric content, volume, taste and color as the TEST drink. The subjects were asked to refrain from any food intake 2 hours prior to exercise and 1 hour post-workout to avoid any influence of foods. There were no other restrictions during the study, other than the 12-hour abstention from food, alcohol and exercise before the body composition and aerobic capacity assessments.

Body composition and aerobic capacity tests were performed on the same day at PRE, MID3, MID6 and POST. The body composition test always preceded the VO₂peak. Body density (BD) was assessed from underwater weighing (UWW) with correction for residual lung volume (RV) using the oxygen dilution method of Wilmore. The average from 2 of 3 trials (within 0.1L) was used as the RV. A submersion tank was used to measure underwater weight in which a nylon swing seat was suspended from a 10 kg Salter scale. The average of the 2 to3 highest weights from 6 to 10 trials was used as the representative underwater weight. Percent body fat (%bf) was calculated from BD using the formula of Brozek.

Aerobic capacity tests consisted of the subjects using a cycle ergometer. After a 5 minute warm-up at 30 W, the subject pedaled at 70 rpm at a power output of 60 W. The power output increased 30 W every 2 minutes until the subject could longer maintain pedaling at 60 W. Expired gas samples were taken at 20 second intervals and the highest VO₂during the test was defined as the VO₂ peak. Within 48 hours of rest after the body composition and aerobic capacity tests, each subject completed a fixed power output endurance test at PRE, MID3, MID6 and POST testing. After a 5 minute warm-up at 30 W, the subject began pedaling at 70 rpm at a power output that corresponded to 90% of the power output at VO₂peak. The subjects were instructed to ride until they could no longer maintain 60 rpm. TTE was recorded as the outcome measurement.

Summary Results/Conclusion

The results of this study indicated that there were no absolute mean differences (p>0.05) between the TEST and CON supplement groups for the training-induced changes in BW, %bf, FFM, VO₂peak or TTE. It is possible that ingesting a CHO-protein supplement immediately after endurance exercise may be more beneficial than CHO alone for aiding in acute muscle recovery and improving performance. However, it is possible that CHO taken alone immediately after endurance training is as effective as a CHO-protein mixture for training-related improvements on aerobic power and endurance performance.

Critique of the Study

This study is definitely one of relevance and one from which athletes of any age/ability can take pertinent information and apply to their respective sport. From previously attained knowledge regarding these specific types of drinks, the results were accurate in the physiological changes, or lack thereof. There is, and always will be constant debate regarding pre, intra, and post-workout nutrition and the most beneficial nutrients and delivery systems. This study is only one small piece of the constantly growing and evolving performance nutrition puzzle.

Practical Application of the Study

Based on the results, post-exercise drinks did not have an affect BW or improve VO₂peak or TTE beyond carbohydrates alone; however they might augment improvements in %bf and FFM during weeks 3-6 of an aerobic exercise program. Perhaps future studies could incorporate higher intensity and volume levels of exercise in order to examine the effects of different relative combinations of CHO, protein and ribose on the training-induced changes in body composition, aerobic capacity and endurance performance. Coaches may also benefit from understanding the CHO, protein and ribose-containing recovery drinks may not provide chronic long-term benefits in aerobic capacity and endurance performance , but they may be useful for improving body composition, more notably, in the earlier stages of training (3-6 weeks) on a cycle ergometer.

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Thread:: A Low Glycemic Index Meal Before Exercise Improves Endurance Running Capacity in Men
Post:: A Low Glycemic Index Meal Before Exercise Improves Endurance Running Capacity in Men
Author:: Christopher Williams

Posted Date:: September 21, 2013 5:53 PM
Status:: Published

Chris Williams

Research Review 1

KINE 5306 – (Advanced Nutrition)

A Low Glycemic Index Meal Before Exercise Improves Endurance Running Capacity in Men

Reference

Wu, C.-L., & Williams, C. (2006). A Low Glycemic Index Meal Before Exercise Improves Endurance Running Capacity in Men.International Journal of Sport Nutrition and Exercise Metabolism, 16, 510-527.

Purpose of Study

The purpose of the study was to investigate the effects of endurance running capacity in men by ingesting a Low Glycemic Index (LGI) or a High Glycemic Index (LGI) carbohydrate (CHO) meal 3 hours before exercise.

Methods and Materials

Eight male recreational runners (age: 28.9 ± 1.5 y; mass: 70.5 ± 2.2 kg; height: 175.0 ± 1.9 cm; VO2max: 60.6 ± 1.5 mL · kg-1 · min-1) completed two trials of exercise after eating either a (LGI) or (HGI) meal. The trails were randomized and separated by 7 days. The subjects fasted for at least 12 hours then ingested the LGI or HGI meal 3 hours prior to running at 70% of their VO2max until exhaustion. Meals consisted of 2 g/kg body mass CHO and were isocaloric and iso-macronutrient with the GI calculated values of 77 for the HGI and 37 for the LGI respectively. The HGI meal was made up of corn flakes, skim milk, white bread, jam, a glucose based drink and water (GI = 77). The LGI meal was made up of All Bran, skim milk, peaches, apples, and apple juice (GI = 37). The run times for the LGI and HGI trials were 108.8 ± 4.1 min and 101.4 ± 5.2 min respectively (P = 0.038). The trails were conducted using a treadmill in the same lab under the exact same environmental conditions.

Samples of expired gas were collected using a Douglas bag via a mouthpiece, respiratory value, nose clip, and tubing at the following times: pre- meal, 15 min, 30 min, 60 min, 90 min, 120 min, 150 min, and 180 min during the postprandial period. During the exercise bout air samples were collected at 15 minute intervals for the first 90 minutes and during the final minute of the run. The ratings of perceived exertion (RPE)(1), perceive thirst (TS), and gut fullness (GFS) were recorded using 6-20 scales. Blood samples were taken during the postprandial period. Additional samples were obtained at 15 min, 30 min, 60 min, 90 min, 120 min and 180 min during the postprandial period, and at 15 min, 30 min, 45 min, 60 min, 90 min, and at fatigue during the subsequent exercise. Energy expenditure, CHO, and fat oxidation rates were estimated from VO2 and VCO2 using stoichiometric equations. The data was analyzed using SPSS and a two-way ANOVA with repeated measures was used to analyze the differences in the biochemical and physiological effects of the trails. For non-time dependent variables, a t-test for paired observations was used with significance set at a .05 confidence level.

Summary of Results and Conclusion

Looking at the aspect of endurance six of the eight subject ran longer when they ingested the LGI meal before exercise. The average running time of the LGI trail (108.8 ± 4.1 min) (range: 84 to 121 min) was significantly longer than HGI trial (101.4 ± 5.2 min) (range: 76 to 120min) (P = 0.038). The LGI trail had higher concentrations of plasma glucose for the first 30 minutes of exercise but there was no differences in glucose after 30 minutes. There was also no real difference in insulin concentrations for the two trails once exercise began. Glycerol levels were higher during exercise for the LGI trails at 45, 60, and 90 min and at fatigue when compared to the HGI trail. There was also no significant differences during exercise of the two trails for the factors of VO2, VCO2, heart rate, or perceived exertion.

The study concluded that ingesting a LGI CHO meal before exercise resulted in a longer run time of about 8 minutes to exhaustion compared to the HGI CHO meal. On the other hand, there was no real significant comparable differences found in the other physiological factors tested. The study suggested that the increase in endurance capacity for the LGI trail may be a result of the greater rate of fat oxidation in the presence of an adequate supply of blood glucose during exercise.

Critique of the Study

The study was very well organized and used the appropriate measures and instruments to make their comparisons and test their hypothesis. Their strict adherence to having all subjects eat the same meals, whether HGI or LGI, warm up in similar fashions, along with pre and post exercise routines, made the test results reliable. Even though the study couldn’t produce enough evidence that eating a particular GI meal before exercise would lead to differences in endurance capacity, it did shed some light on the fact that LGI meals may give endurance runners an advantage. One aspect of the study that should be addressed is the need to test female subjects. Testing of the different sexes may lead to new findings that are still unclear in this area of study.

Practical Application of the Study

Most endurance runners are very conscious of their endurance capacities and are always looking for an edge. I believe this study will assist distance runners in evaluating their meal choices before exercise. When meal planning, coaches and distance runners may use this study to help them understand the importance of ingesting LGI meals on training and race days.

Questions

What would the differences be in the test subject’s physiological factors if they were to use a completely anaerobic exercise test?

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Thread:: Hydration Status,Fluid Intake and Electrolyte Losses in Youth Soccer Players
Post:: Hydration Status,Fluid Intake and Electrolyte Losses in Youth Soccer Players
Author:: Hickel Woolery

Posted Date:: September 22, 2013 12:44 PM
Status:: Published

Hickel Woolery

KINE 5306 – Advanced Nutrition

Dr. Kelly Brooks

Sunday, September 22, 2013

Williams , C., & Blackwell, J. (2012). Hydration status,fluid intake and electrolyte losses in youth soccer players.

International Journal Of Sports Physiology and Performance , 7, 367-374.

Purpose of study

Most data on fluid intake and body mass changes have been collected in warm or hot environments. Guidelines for hydration has been structured from mostly research in warmer environments, these guidelines are used to help athletes prevent or reduce the risk of heat illness and to optimize performance. It is unclear whether these guidelines are applicable to athletes who compete and train in cooler environments. The purpose of the study was to determine the hydration status, fluid intake, and electrolyte losses of 21 male professional youth soccer players (age 17.1 ± 0.7 y) training in a cool environment.

Methods and materials

Twenty-one professional male youth soccer players from the academy in southwest of England (age 17.1 ± 0.7, height 1.75 ± 0.05 m, body mass 69.2 ± 7.4 kg) volunteered to participate in

This study. Players were asked to maintain their normal daily routine before and during training sessions,the anthropométrie measurement of height was collected (Seca stadiometer

SEC-225, Seca, Hamburg, Germany) upon their arrival to the training ground, urine samples were then taken for analysis. The color of the urine was assessed using a 1 to 8 urine-color chart scale. The samples were also analyzed for osmolality by the freezing-point method using an osmometer.

The Athletes were then weighed wearing underpants only, using digital scales. Their water bottles and other personal sport drink bottles were also weighed using a food scale. Absorbent patches containing adhesive nonporous film were applied to the Chest (pectoral), back (midscapula), thigh (lateral), and arm (triceps), these absorbent patches were used to collect sweat.

The training session lasted 100 minutes and included various drills and competition simulation matches. Training took place around 10:20 am and the environmental conditions were dry, overcast with a temperature of 11.0 ± I.2°C, humidity 50% ±3.3%, and wind speed 0.5-1.5 km/h. During the training sessions players were monitored and advised to only drink from their bottles and to reduce spillage. After the training session the absorbent patches were carefully removed and placed in a Centrifuge tube and stored at 4°C. Analysis was done by Centrifuging samples at 10,00g for 10 minutes, the sweat was diluted 1000- fold in ultrapure water followed by flame-emission spectroscopy to determine sodium and potassium ion concentrations, then diluted another 100-fold and analyzed by atomic –absorption spectroscopy for magnesium ion concentration. Values were obtained by plotting absorbance against a standard curve derived from 4 concentrations of known amounts. Two player’s samples were too low so sweat analysis was only done on 19 players. The players also had their body mass measured and provided a second urine sample after the training session. Total fluid loss was calculated as body sweat loss plus urinary output minus total fluid intake. Sweat volume was calculated from the changes in body mass (corrected for the fluid intake) and urine volume, 2 post training urine samples were spoiled during transportation to the laboratory, so all osmolality analyses were completed on 19 players.

Summary of results /Conclusion

Pre-training body mass was significantly different from post training body mass (69.2 ± 7.4 kg and 68.8 ± 7.2 kg,P <0001, n^2^ - 0.48). The mean difference between pre-training and post training was 0.4 kg (90% CI 0.23-0.49Kg); Mean fluid intake was 807 ± 557 mL (range 0-1700 mL), this could be a reason for the body mass change.

There was no significant change in urine color from pre-training to post training, however there was a substantial difference in the osmolality measurement from pre-training to post- training, 1319 (+/-) 525 pre training and 687 (+/-) 389 mOsmol/kg. Fourteen players provided pre-training urine samples with an osmolality greater than 900 mOsmol/kg, but only 4 of these players remained hypohydrated at the end of the training session.

There was no significant correlation between the changes in osmolality and sweat loss, there was no significant correlation between osmolality and fluid intake. This research showed that there are similarities among adolescent soccer players training in cool conditions and other studies in warmer conditions. Adult athletes being hypohydrated before training seems to be common among youth players as well. Measurements of urine color pre-training and post training did not adequately reflect players changing hydration status. Therefore it is important for coaches and support staff to educate athletes on hydration pre-training as well as stressing hydration to their athletes in cold environments as well.

Critique of The Study

By using so many different techniques to obtain samples, there can be room for contamination and incorrect measurements. The sample size could also be larger. Since the test subjects were only males, would results differ for adolescent females? Did education about the purpose of the study influence the participants drinking above their average fluid intake for this study? Overall this was a very good research as it relates to hydration and the different methods allow a greater insight into why hydration is important.

Practical Application of the study

Most athletes take hydration for granted in cooler environments, this research can be useful in reminding athletes that it is equally important to hydrate in cool weather as in warm weather. Caution must also be used when solely checking urine color to determine hydration as well. Coaches and support staff must reinforce hydration to their athletes in such conditions because doing so will prevent the athlete from taking hydration for granted when in cool environments. This is applicable to almost every athlete since most sports training session or competition period occur at some point during cool weather.

Attachment: File

Hydration Status,Fluid intake and Electrolyte Losses in Youth Soccer Players.pdf (8.252 MB)

Research and Rants on Performance

Wednesday, October 9, 2013

Sport Nutrition Current Research Review

Reference

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