The aim of the study was to investigate the effect of high energy diets, which were elaborated by the study authors, on the change of physical fitness of athletes of various sports. 90 athletes aged 17–30 years participated in the research. They were divided into three groups of 30 each. Our research has shown that prepared high-energy diets, used during 3 months in the preparatory period, per week-long training microcycles, had a greater positive effect on changes in the fitness of elite athletes of various sports compared to changes in the fitness of lower-performance athletes.

Purpose: The aim of the study was to evaluate the mode and the eating habits of some sports athletes as well as to find out the sources of received knowledge about nutrition athletes. Material: In the evaluation of actual nutrition in 2017, 60 participants took part, including 15 volleyball players of the Burevestnik team, 15 judo wrestlers of the national team of Kazakhstan, 15 wrestlers of the club team and 15 triathletes of the national team of Kazakhstan. To study data on the regime and eating habits, a valid questionnaire was used, directly interviewing each researcher. The statistical analysis of the survey data was carried out, the percentage distribution of responses on the questionnaire was calculated. For the analysis of categorical data χ2 test (chi-square) have been applied. Results: The results of the study have shown that Kazakhstan sportsmen diet is not optimal, not enough of the studied athletes eat 4 or more times a day. 22.7% of the respondents are snacking not enough - only once per day, and 11.7% of the respondents do not snack at all. More than half of the subjects (52%) regularly eats every day at the same time, while 48% - not always eat regularly. Conclusions:The main criterion for the selection of food is taste, paying too little attention to the specificity of sport and on a special diet. Basic information about nutrition investigated Kazakh athletes receive from coaches and family members, and the share of doctors and nutritionists have to too small impact here. Public information systems are relatively ineffective.