[The structure of blood gut microbiota markers in athletes and their relationship with the diet].

It is known that under conditions of ultra-high physical activity and a specific diet, the state of the microbiota plays a significant role in maintaining the health, metabolic and energy status of athletes. The purpose of the study was to evaluate the composition of blood microbial markers in professional football players and physically active people and their correlation with diets in order to substantiate recommendations for their optimization. Material and methods . In a cross-sectional study a group of football players (n=24, 28±3 years old, body mass index - 22.5±1.0 kg/m 2 ) who received a diet according to the training regimen, and a comparison group of physically active individuals (n=25, 34±5 years old, body mass index - 21.8±2.8 kg/m 2 ) have been examined. The method of gas chromatography-mass spectrometry was used to analyze microbial markers of microbiome, mycobiome, virome and blood metabolome populations. Data on actual dietary intake were collected using food diaries for 3 days, followed by data processing with the Nutrium 2.13.0 nutritional computer program. For analysis, individual daily requirements for energy and macronutrients have been calculated based on the basal metabolic rate (according to the Mifflin-San Geor formula, taking into account anthropometric data), the coefficient of physical activity (groups IV and II, respectively). Results . The analysis of the athletes' diet, compared with individual requirements and with the recommendations of the International Society for Sports Nutrition (ISSN), revealed a lack of complex carbohydrates (5±1 instead of 6.1±0.3 g/kg body weight day), an excess of sugars (23±4 instead of <10% of kcal). These figures are significantly higher than the intake of similar nutrients in physically active people in the comparison group. In football players, compared with the comparison group, significant changes in microbial markers were found for Alcaligenes spp., Clostridium ramosum, Coryneform CDC-group XX, Staphylococcus epidermidis (p<0.001), known for their pro-inflammatory activity in the intestine, as well as for Lactobacillus spp. (p<0.001) performing a protective function. In addition, mycobiome markers were increased in athletes: Candida spp. (p<0.001), Aspergillus spp. (p<0.001), among which there are potential pathogens of mycoses. This was not observed in the comparison group. At the same time, an increase in the microbial markers of Alcaligenes spp., Coryneform CDC-group XX, Lactobacillus spp., Streptomyces spp., Candida spp. Micromycetes spp., containing campesterol in the cell wall, in football players positively correlated with a high calorie diet (p<0.001). A similar correlation of mycobiome markers (Micromycetes spp., containing sitosterol in the cell wall, ρ=0.346, p=0.015) was observed with an excess of easily digestible carbohydrates. Taking into account the data obtained, a correction of the diet have been proposed: increasing the consumption of carbohydrates to 7.3-7.5 g/kg of body weight/day by including bakery products from whole grain flour and cereals in the diet (up to 300-370 g/day), limiting simple sugars (up to 90-95 g/day). Conclusion . High physical activity leads to changes in the structure of blood microbial markers, including a shift towards an increase in potentially pathogenic fungi. Wherein, a predictive role is played by an imbalance of macronutrients in terms of quantitative and qualitative composition, an excess of simple sugars, and a lack of slowly digestible carbohydrates. To correct the diet, an additional inclusion in the diet of their main sources - products from cereals (cereals and bakery products) is proposed.