Gut microbiota of sprint athletes: signature microbes and dietary links.

BACKGROUND: The gut microbiota has emerged as an important biological factor associated with host physiological status in athletes. However, relevant research remains limited for sprint athletes, whose physiological demands differ substantially from those of endurance athletes. OBJECTIVE: This study aimed to characterize the gut microbiota profile of college sprint athletes, compare it with non-athletic peers, identify potential sprint-associated bacterial taxa, and explore diet-microbiota associations to propose potential nutritional hypotheses for these signature taxa. METHODS: Fecal samples were collected from 20 college sprint athletes and 23 non-athletic college students for metagenomic sequencing. Dietary intake was assessed using a validated food frequency questionnaire. Alpha and beta diversity analyses were performed to evaluate microbial community diversity and structure. LEfSe was used to identify differentially abundant taxa. Functional annotation and enrichment were conducted using KEGG, GO, and other databases. Spearman's correlation was applied to examine diet-microbiota relationships. RESULTS: Alpha diversity indices (Shannon, Chao1, etc.) did not differ significantly between groups. In contrast, beta diversity analysis revealed significant structural separation. LEfSe identified Segatella copri (LDA = 4.986, p = 0.017) and Bifidobacterium adolescentis (LDA = 3.154, p = 0.003) as signature taxa in athletes, both with significantly higher abundance than in non-athletes. Functional analysis showed predicted enrichment of pathways related to energy metabolism (carbohydrate metabolism, ATP binding) and amino acid metabolism in athletes. Correlation analysis indicated that S. copri abundance was nominally positively associated with dairy intake (r = 0.31, p = 0.045), while B. adolescentis was nominally associated with whole grains, soy milk/soy powder, and dairy products. CONCLUSION: College sprint athletes possess a distinct gut microbiota structure compared with non-athletes. S. copri and B. adolescentis represent distinct microbial signatures associated with sprint athletes, accompanied by corresponding predicted functional pathway enrichment. Specific dietary patterns, including the intake of whole grains, soy milk/soy powder, and dairy products, exhibit exploratory nominal associations with the signature gut microbiota composition of sprinters.