Acute Effects of Caffeine Intake on Psychological Responses and High-Intensity Exercise Performance
What this study found
Acute caffeine produced beneficial effects on mood, vitality, high-intensity performance, and post-exercise perceived exertion. Compared with placebo, subjective vitality was higher (38.67 ± 4.37 vs 36.00 ± 5.77; p = 0.024), POMS tension was higher (6.80 ± 5.78 vs 3.60 ± 2.90; p = 0.004), and POMS vigor was higher (13.20 ± 3.23 vs 11.87 ± 3.04; p = 0.010). Caffeine also improved Wingate performance, increasing peak power (11.72 ± 0.85 vs 11.39 ± 0.98 W/kg; p = 0.039), average power (8.97 ± 0.70 vs 8.77 ± 0.63 W/kg; p = 0.028), and shortening time to peak power (7.07 ± 1.33 vs 8.73 ± 1.49 s;…
- Study & population
- Randomized crossover, placebo-controlled trial in 15 resistance-trained male undergraduate students in Physical Activity and Sport Sciences.
- Intervention
- A single acute oral dose of caffeine 6 mg/kg was administered as capsules and compared with an identically dosed placebo of sucrose 6 mg/kg.
- Key limitation
- The sample was small and restricted to young resistance-trained men, limiting generalizability.
Original abstract
Objective: The aim of this study was to investigate the effects of caffeine supplementation on: (i) psychological responses of subjective vitality and mood; (ii) performance through a Wingate test; and (iii) rate of perceived exertion (RPE) reported after a Wingate test. Methods: Fifteen male participants (22.60 ± 2.16 years) ingested 6 mg·kg-1 of caffeine or placebo (sucrose) supplementation in two experimental sessions. After 60 min from supplement intake, participants fulfilled two questionnaires, which measured subjective vitality and mood state, respectively. Subsequently, participants’ performance was assessed through a Wingate test, which was followed by measurements of RPE at general, muscular, or cardiovascular level. Results: Caffeine supplementation increased some components of mood, as assessed by profile of mood states (POMS) (tension and vigor dimensions) and subjective vitality profiles, which were followed by a greater maximum power, average power, and lower time needed to reach maximum power during the Wingate test. Moreover, lower RPE, both at muscular and general levels were reported by participants after the Wingate test. Conclusions: These results suggest that caffeine supplementation exerts positive effects both in psychological and physical domains in trained subjects.