Can CYP2D6 help with Sport?

CYP2D6 is a drug-metabolizing enzyme primarily expressed in the liver. It processes many medications, including beta-blockers, opioids, and some antidepressants. There is no strong evidence directly linking CYP2D6 variants to athletic performance. Some research suggests minor effects on caffeine metabolism or painkiller response, which could theoretically influence training or recovery, but these effects are small and not clinically meaningful. Athletic performance is far more influenced by training, nutrition, sleep, and other genetic factors (e.g., ACTN3, PPARGC1A). A CYP2D6 test is not useful for sports optimization. Caveat: CYP2D6 may affect how certain drugs used in sports (e.g., analgesics) are metabolized, but this is a pharmacogenetic, not a performance-genetic, consideration. No clinical recommendation.