Characterization of the Gut Microbiota Signature According to Physical Fitness and Its Implications for Intestinal Health.

The gut microbiota comprises all microorganisms inhabiting the digestive tract, evolving throughout life under the influence of various intrinsic and extrinsic factors. Under healthy conditions, the microbiota remains stable, resilient, and maintains a symbiotic relationship with its host. Conversely, dysbiosis refers to an alteration in microbial composition and function, which has been linked to diseases such as inflammatory bowel disease (IBD). IBD, including Crohn's disease and ulcerative colitis, is associated with a disrupted microbiota compared to healthy individuals, leading to impaired intestinal barrier integrity and activation of local inflammatory pathways. Increasing evidence also suggests that the gut microbiota of athletes differs from that of physically inactive individuals, showing greater microbial diversity and higher concentrations of short-chain fatty acids (SCFAs). In this context, the present clinical study aims to characterize the bacterial metagenome of the gut microbiota across a continuum ranging from inactive individuals to elite athletes with high or very high energy demands. The ultimate goal of this project is to determine whether specific gut microbiota composition and functional profiles are associated with different levels of exercise capacity, and to create a fecal microbiota biobank for future research on intestinal health.

NCT Number	NCT07276464
Lead Sponsor	University of Rennes 2
Conditions	Healthy
Enrollment	30 participants
Start Date	2025-11-17
Primary Completion	2026-05-09 (estimated)
Study Completion	2026-06-18 (estimated)
Updated on ClinicalTrials.gov	2026-06-23