Proceedings of the Thirteenth International Society of Sports Nutrition (ISSN) Conference and Expo

Meeting Abstracts: Proceedings of the Thirteenth International Society of Sports Nutrition (ISSN) Conference and Expo Clearwater Beach, FL, USA. 9-11 June 201

Effects of skim milk and isotonic drink consumption before exercise on fluid homeostasis and time-trial performance in cyclists: a randomized cross-over study

Background Hydration status affects endurance performance. Pre-exercise hydration recommendations target the consumption of high carbohydrate and sodium beverages. Milk, due to its carbohydrate and sodium content, may be considered an effective pre-exercise hydration beverage. Purpose In a randomized cross-over trial, we compared the effects of an isotonic sport drink (SPD) with skim milk (SM) consumption before a race, on fluid homeostasis and time-trial performance in road cyclists. Methods Male road cyclists (n = 9; age, 26.8 ± 4.78 years) with 10.8 ± 8.56 years of experience in national competitions, consumed either SPD or SM in doses of 350 mL at 3 h and 350 mL at 1.5 h before a 18.6 km time-trial race. Measurements of body mass, urine specific gravity (USG), urine color and time-trial were compared between drinks (group; g) before and after the race (time; t). Results The two-way ANOVA showed no differences between SPD and SM in body mass (t, p < 0.0001; g, p = 0.89; t × g, p = 0.54), USG (t, p = 0.01; g, p = 0.63; t × g, p = 0.29) and urine color (t, p = 0.01; g, p = 0.54; t × g, p = 0.28) before or after race. Furthermore, no differences on water consumption during the race (p = 0.55) or time-trial performance (p = 0.84) were observed between trials. Conclusion Current results may help athletes with different beverages preferences to increase their options of hydration strategies

Somatotype and polymorphism of the ACTN3 and ACE gene in Chilean table tennis players

Introduction.The study of anthropometric and genetic variables are essential as determinants of sports performance. Objective.The objective of the study was to determine the somatotype and the frequency of genotype and allele of 506B-actinin 3 (ACTN3) R577X and angiotensin converting enzyme (RCT) I / D polymorphism of Chilean table tennis players. Method. 24 male table tennis players (age 22.1 x 5.4) of Chile's national rankings were studied. Obtaining ACTN3 and ACE was collected by sample of saliva and analyzed by polymerase chain in real time.The body structure was characterized through the somatotype method proposed by Carter. From descriptive statistics, the mean values of somatotype, frequency of classification and location of somato letter were analyzed, in addition, of genotype frequency values and allele of ACTN3 R/X and ECA I/D polymorphism according to number of occurrence and percentage. Results. It demonstrated a predominance of mesoendomorphy and endomorphy classification, a higher phenotypic frequency XX with predominance of allele X for the ACTN3 gene and higher frequency of DI allele with predomina D for ACE. Conclusion.The somatotype of Chilean tenimestists has an orientation towards mesoendomorphy and a predominance of the genotype XX and allele X of the ACTN3 gene and, predominance of the DI genotype and allele D of the ACE gene, these characteristics could offer a genetic advantage in terms of strength levels and muscle potency, possibly facilitating practice and competitive success in these Chilean tenimists