The combination of sport and sport-specific diet is associated with characteristics of gut microbiota: an observational study.

Lae-Guen Jang, Geunhoon Choi, Sung-Woo Kim, Byung-Yong Kim, Sunghee Lee, Hyon Park

Journal: Journal of the International Society of Sports Nutrition 2019;16(1):21

PMID: 31053143

Plain Language Summary

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Regular exercise offers many health benefits. Research also suggests that regular exercise plays a beneficial role for the structure and diversity of gut microbiota. However, diets high in monosaccharides (simple sugars) and protein, and low in fibre, which are commonly consumed by athletes may have a negative effect on the gut microbiota. The aim of this observational study was to investigate the long-term effects of a specific exercise type and athletes’ diets on gut microbiota. 15 men in their 20s who were bodybuilders, elite distance runners or healthy controls without regular exercise habits were recruited for this study. Gut microbiota characteristics, dietary intake, and body composition were compared. There were significant differences in body composition according to exercise type and dietary habits, with bodybuilders having most lean tissue and distance runners the lowest body fat percentage. Dietary patterns were characterised by high protein intake for bodybuilders and low fibre intake for distance runners. Fat consumption did not vary between groups. Gut microbiota diversity did not differ between groups but there were differences in the relative abundance of certain intestinal microbes, with potentially negative effects.

Abstract

BACKGROUND

Recently, gut microbiota have been studied extensively for health promotion, disease prevention, disease treatment, and exercise performance. It is recommended that athletes avoid dietary fiber and resistant starch to promote gastric emptying and reduce gastrointestinal distress during exercise, but this diet may reduce microbial diversity and compromise the health of the athlete's gut microbiota.

OBJECTIVE

This study compared fecal microbiota characteristics using high-throughput sequencing among healthy sedentary men (as controls), bodybuilders, and distance runners, as well as the relationships between microbiota characteristics, body composition, and nutritional status.

METHODS

Body composition was measured using DXA, and physical activity level was assessed using IPAQ. Dietary intake was analyzed with the computerized nutritional evaluation program. The DNA of fecal samples was extracted and it was sequenced for the analysis of gut microbial diversity through bioinformatics cloud platform.

RESULTS

We showed that exercise type was associated with athlete diet patterns (bodybuilders: high protein, high fat, low carbohydrate, and low dietary fiber diet; distance runners: low carbohydrate and low dietary fiber diet). However, athlete type did not differ in regard to gut microbiota alpha and beta diversity. Athlete type was significantly associated with the relative abundance of gut microbiota at the genus and species level: Faecalibacterium, Sutterella, Clostridium, Haemophilus, and Eisenbergiella were the highest (p < 0.05) in bodybuilders, while Bifidobacterium and Parasutterella were the lowest (p < 0.05). At the species level, intestinal beneficial bacteria widely used as probiotics (Bifidobacterium adolescentis group, Bifidobacterium longum group, Lactobacillus sakei group) and those producing short chain fatty acids (Blautia wexlerae, Eubacterium hallii) were the lowest in bodybuilders and the highest in controls. In addition, aerobic or resistance exercise training with an unbalanced intake of macronutrients and low intake of dietary fiber led to similar diversity of gut microbiota. Specifically, daily protein intake was negatively correlated with operation taxonomic unit (r = - 0.53, p < 0.05), ACE (r = - 0.51, p < 0.05), and Shannon index (r = - 0.64, p < 0.01) in distance runners..

CONCLUSION

Results suggest that high-protein diets may have a negative impact on gut microbiota diversity for athletes, while athletes in resistance sports that carry out the high protein low carbohydrates diet demonstrate a decrease in short chain fatty acid-producing commensal bacteria.

Address: Exercise Nutrition & Biochemistry Lab., Kyung Hee University, Yongin, Republic of Korea.; Growth and Aging Lab., Kyung Hee University, Yongin, Republic of Korea.; ChunLab, Inc., Seocho-gu, Seoul, Republic of Korea.; Research Lab., Ildong Pharmaceutical Co., Ltd., Hwaseong, Republic of Korea.; Exercise Nutrition & Biochemistry Lab., Kyung Hee University, Yongin, Republic of Korea. [email protected].

Patient Centred Factor

Clinical Imbalances

Laboratory Testing

Modifiable Lifestyle Factors

Nutrition Evidence Keywords

Bioactive Substances

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