The effect of napping and caffeine on physical performance following one night of sleep restriction

Michelle Goldberg

Abstract

PURPOSE: To assess the effects of caffeine napping on 3-km time trial performance and peak muscle strength. METHODS: Nine college-aged participants visited the lab for three separate visits. For each visit, participants ingested a caffeine (CAF) or placebo (PLA) pill, followed by a nap for one of the visits (CAFNAP), and completed a Karolinska Sleepiness Scale (KSS) and Stroop test for a cognitive assessment, a peak strength test and a 3-km time trial (TT). The peak strength test assessed peak isokinetic leg extension strength. The 3-km TT was computer simulated with completion time and average power output being assessed. KSS data was analyzed using the Friedman Test, and all other measures were analyzed with a One Way Reported Measures ANOVA. RESULTS: Power output during the 3-km TT was the only measure that resulted in a difference between CAFNAP and PLA (p=.042). All other measures had no differences between any treatments (p=.075) CONCLUSIONS: Caffeine napping has little to no effect on physical or cognitive performance other than on power output during a 3-km TT.