Evidence check: Stuhlprobe in the context of Sport

Stool sample analysis in the context of sports is often marketed as a tool to optimize performance by tailoring the gut microbiome. However, current scientific evidence is mostly mechanistic or derived from animal studies; robust human trials with athletic endpoints are scarce. MyBody-X offers a gut microbiome test, but according to the provided context its evidence level is rated as 'marketing' – it cannot diagnose leaky gut nor provide directly actionable training or nutrition advice. For endurance athletes, a link between microbiome composition and performance is plausible (e.g., influencing inflammation, energy harvest), but individual predictive power is low. A single stool sample captures a snapshot of bacterial composition, heavily influenced by diet, daily variation, and probiotic use. Without repeated measurements and clinical correlates, conclusions about athletic readiness are speculative. Safety note: Stool tests are not a substitute for medical evaluation of gastrointestinal issues. Athletes serious about performance improvement should rely on validated methods such as blood tests (e.g., vitamin D, iron status) and sports medicine guidance. Evidence grade: marketing/unclear.