How are Stuhlprobe and Sport related?

The provided knowledge contexts do not directly link stool samples and sport. One context discusses athletic performance in relation to CYP1A2 genotype and caffeine, but without any mention of stool samples. Stool samples are commonly used for microbiome analysis, which may indirectly affect athlete health and performance, but this is not addressed in the given sources. Therefore, the evidence is unclear, and no specific relationship between stool sample and sport can be derived from the context.