The Effect of Habitual Caffeine Use on Strength, Power, and Muscular Endurance Performance in Collegiate Athletes

ABSTRACT: Jump, IP, Hsu, H-S, Roberts, MD, and Oliver, GD. The effect of habitual caffeine use on strength, power, and muscular endurance performance in collegiate athletes. J Strength Cond Res XX(X): 000-000, 2026-Caffeine has been shown to increase strength, power, and muscular endurance performance in trained athletes, but individual variation can persist. One belief for this variation is the habituation of caffeine, which may influence how individuals respond to an acute caffeine dose. The current research on this topic is sparse and has produced mixed findings. The purpose of this study was to investigate how habituation to caffeine influences the ergogenic effects on strength, power, and muscular endurance. Twenty-one NCAA Division III baseball players completed a double-blind, randomized, within-participant crossover design (age = 20 ± 1 years old; mass = 87.2 ± 8 kg). Three weeks before testing, subjects completed daily caffeine intake questionnaire. Subjects were classified as habitual or nonhabitual users using a sample mean split. Each subject completed 2 experimental trials, separated by 72 hours, consisting of a vertical jump, trap bar deadlift 1 repetition maximum (1RM), bench press 1RM, and a pull-up test to failure. Trials followed identical procedures under 2 conditions: ingestion of caffeine (3 mg·kg-1) or placebo. Performance outcomes were analyzed using two 2 × 2 mixed ANOVAs to test the main effects of the condition and the condition × group interaction. Linear regression analyses examined average caffeine intake as a predictor of standardized performance change. Significant was set to p ≤ 0.05. Caffeine had no significant effect on performance, and no condition × group interaction was detected. Lower dose caffeine supplementation did not enhance performance outcomes in college male athletes, and habituation to caffeine did not influence these null effects.