Student Replies/Glycemic Index and Sports Performance
Students were to For this forum, we will discuss the efficacy of the glycemic index for athletes. Find one research article on the glycemic index and exercise or athletic performance and investigated the effect of different glycemic diets on endurance or performance. Please continue the discussion by following-up with two other students' posts Student 1For this week’s forum I chose an article that looked at the differences in a high or low glycemic index meal after exercise. The researchers wanted to know if the differences in this meal would affect sleep quality and the following day’s exercise performance. This article cited that almost half of athletes suffer from poor sleep. Sleep being a determining factor in exercise recovery and performance post sleep, the researchers wanted to look at the efficacy of diet interventions on sleep. They used 10 recreationally trained men in their lower 20s who train using high intensity and have been training at least three times a week of the past two years. Baseline data was taken on each participant and each was given a nutrition plan to follow throughout the day. On the day of the experiment, the participants ate a standardized meal three hours prior to showing for their exercise performance. Once they showed to the lab, each participant performed a high intensity workout on a stationary bike. Following the workout, each participant was randomly assigned either a high or low glycemic meal. After two hours each participant went to bed and their sleep was analyzed using a polysomnography in their homes. Upon waking they ate a standard breakfast and three hours later performed another exercise assessment on the bike as well as a countermovement jump test and a visual reaction time test. The researchers used a seven-day washout period and then began another trial using the opposite meal. This study found that a high glycemic meal following exercise can help to not only increase sleep time, but can also increase sleep efficiency. The high glycemic meal also had a significant improvement in the visual reaction time test. The results for the following day performance showed no significant difference between the two meals. The researchers concluded that a high glycemic meal may help people with sleep issues and further testing needs to be done. I believe this study did a decent job on their conclusions and tests. It is always good to control a person’s entire diet, but it can’t always be accomplished. That being said, the researchers did a good job controlling the pre and post workout meals. I would have liked to have seen some test for power built into this study, but they did a good job testing performance. Sleep, like nutrition, is one of the main pieces of health that I see people neglecting. Finding a way to get longer, more efficient, sleep through diet could be very valuable. Bibliography: Vlahoyiannis, A., Aphamis, G., Andreou, E., Samoutis, G., Sakkas, G., & Giannaki, C. (2018). Effects of High vs. Low Glycemic Index of Post-Exercise Meals on Sleep and Exercise Performance: A Randomized, Double-Blind, Counterbalanced Polysomnographic Study. Nutrients,10(11), 1795-1808. doi:10.3390/nu10111795 Student 2 This week we are looking at sports driven nutrition. I have chosen an article by Little, Chilibeck, Ciona, Vandenberg, and Zello, (2009) titled “The Effects of Low-and High-Glycemic Index Foods on High-Intensity Intermittent Exercise.” The purpose of their research was to study what effects low and high glycemic index foods would have on metabolism and functioning during high intensity intermittent exercise (such as team sports). In their study, the researches wanted to imitate exercise comparable to a soccer game. Researchers wanted to prove that eating a low glycemic index (GI) food 3 hours before and halfway through a 90-minute match would improve “maintenance of blood glucose and promote higher fat oxidation during exercise compared with a high-GI food…” (Little et al., 2009). Consequently, performance would improve near the end of the game. This study consisted of 7 experienced male athletes who participated in a total of 3 trials each separated by approximately 7 days. This was a single-blinded experiment in which the participants did not know the experimental conditions but were aware of which foods they were eating. The low GI food and the high GI food were matched in macronutrients. I found this to be interesting because this is the first article I have selected in this class that actually specified this. I think it is important since it leaves less “guessing” when looking at the results of the study. For the low GI food, they used lentils which they approximate to have a GI of 29 as compared to instant mashed potatoes, egg whites and ketchup as the high GI food, GI of 81. Researchers concluded that high GI carbohydrates did impair fat oxidation, but there was no difference in performance. They also concluded that they did not find a difference in “substrate oxidation or blood glucose concentration during exercise” (Little et al., 2009). It should be noted that most participants were initially unable to consume all their food and on the second trial those amounts were modified accordingly. Although the sample is small, I think by using athletes who were experienced in treadmill running was a good representation of those that would be playing such sports like soccer and rugby. Reference: Little, J. P., Chilibeck, P. D., Ciona, D., Vandenberg, A., & Zello, G. A. (2009). The Effects of Low-and High-Glycemic Index Foods on High-Intensity Intermittent Exercise. International Journal of Sports Physiology & Performance, 4(3), 367–380. Retrieved from http://search.ebscohost.com.ezproxy2.apus.edu/login.aspx?direct=true&AuthType=ip&db=s3h&AN=43913447&site=ehost-live&scope=site 150 words for each student, supporting sources APA, Due Fri May 31 at 1155 pm EST.