By Alex Hutchinson on
A gene that affects how quickly you metabolise caffeine may affect whether it helps or hurts your race times.
Caffeine is the universal performance-booster: it works for all distances, all sports and all people.
At least, that’s what I used to think. But a session at the American College of Sports Medicine annual meeting earlier this month offered a surprising caveat to that blanket statement. Caffeine, it appears, works for ...