Sample Size Determination
A priori, a sample size of 50 was selected, with a goal of 20 per treatment group (PRO, PRO + FB) and 10 in the CON group. This sample size was informed by a power analysis using the partial eta-squared effect size for the BFP group × time interaction reported in a previous trial examining the effects of chronic consumption of placebo, non-caffeinated, and caffeinated dietary supplements [