The Influence of Caffeine and Guarana on Dehydration of Young Soccer Players and Physiological Aspects of Dehydration of the Athlete's Body

[摘要] Introduction The aim of the study was to assess the effect of caffeine and caffeine with guarana on the dehydration of young soccer players and the effect of dehydration on their reaction time. Material and Methods The study involved 57 players aged 16.8 ± 0.5 years, with an average body weight of 66.5 ± 9.3 kg, and height 178 ± 6.7 cm. An analysis of the body composition was performed. Thus, the results regarding body weight, adipose tissue, muscle tissue, BMI and body hydration were obtained. Next, the competitors performed successively a test for reaction time and speed over a distance of 5 and 15 meters with the use of photocells. After the tests, the players were randomized into 3 groups, where they received 200 mg caffeine, caffeine + guarana (200 mg + 40 mg), and placebo. Then, the players participated in a soccer training of medium intensity on the pitch, which lasted about 60 minutes. Immediately after completing the training, the procedure for testing reaction time and speed as well as body composition analysis were repeated.

[关键词] caffeine in sports;supplementation;dehydration in sport;athlete's diet;nutrition in sport;football;soccer