Supplementswell supported · human dataDiscovery of the day
Across 23 double-blind trials in trained cyclists, pre-exercise caffeine cut time-trial completion time with a small effect and zero heterogeneity, in both short efforts of 10 minutes or less and long ones of 20 minutes or more. Mean power output rose significantly only in the short trials.
What it shows: Meta-analysis of 23 randomised, double-blind, placebo-controlled trials in healthy cyclists; effects are small (SMD −0.32 for completion time) and the subgroup difference between short and long trials was not statistically significant.Systematic review · Front Physiol