Jon-Kyle Davis*, Matt Green, Matt Laurent, Nick Bacon and Whitney Thomas
A double-blind, placebo controlled, randomized trial was performed to evaluate the effects of a nutritionally enriched coffee (NEC) drink compared to decaffeinated coffee (DC) on repeated flying 40-yard sprint performance.
Physically active male and female volunteers (n = 13) completed 24 × 50 yard sprints following NEC and DC (counterbalanced). Sprints were completed in 2 halves(12 sprints per half) with 2 minutes recovery between each sprint and a 10-minute recovery period between halves. Acute-RPE (A-RPE) (0–10 omni scale) was recorded after every sprint and Session RPE (S-RPE) was recorded 20 min after completing each trial. Blood lactate ([LA]) was recorded at baseline and following sprints, 6, 12, 18, and 24. Additionally, a fatigue index (FI) was calculated as a percentage difference between mean sprint time and fastest sprint time.
A 2 (trial) × 2 (treatment) repeated measures ANOVA revealed significantly (p = 0.03) faster (main effect) sprint time for NEC. Post-hoc analyses revealed significantly faster times (p ≤ 0.05) for sprints 1, 3, 4, 6, 8, and 17, while approaching significance at sprints 10 (p = 0.07) and 15 (p = 0.08). No main effect for A-RPE (p = 0.28) or [LA] (p = 0.15) was found. Results from a paired t-test revealed a significantly improved FI (p = 0.04) with NEC but no significant impact on S-RPE (p = 0.72).
Results indicate that caffeine administered in a NEC drink can enhance repeated bouts of acute sprint performance possibly through delayed fatigue as evidenced in a dampened perceived exertion response (faster sprints with similar RPE).
The findings of this study appear to give a reason for physically active males and females to consume nutritionally enriched coffee before any repeated bouts of sprints to enhance their performance by blunting their perception of fatigue. I don’t feel that regular gym goers who workout in the afternoon would be crazy about performance enhancing through coffee. However, this coffee could be beneficial for the morning rush gym rats. After reading this abstract I had a few questions. First would be could these results translate to elite athletes, I know for a fact that at Penn State when the football players come back from summer break they must run 15 40 yard dash all within .2 seconds of their best. If this nutritionally enhanced coffee could dull their perception of fatigue they might be able to pass this test easily. Also I am assuming that the participants consumed JavaFit coffee, how much coffee did the subjects consume? And how many mg of caffeine? Other than these questions it appears that this enhanced coffee may be very beneficial especially to gym goers early in the morning, one to offset fatigue and two psychologically ( I know I can’t function until I have my cup of coffee.)