Dose-response Benefits Of Caffeine Ingestion On Sprint Performance During High-intensity Exercise

Abstract

The ergogenic effect of caffeine on endurance performance is well documented at moderate doses (∼ 6mg·kg-1 body weight), although low doses of caffeine (< 3mg·kg-1 BW) have failed to improve endurance performance. In contrast, there is less information regarding the dose-response benefits of caffeine on anaerobic performance. PURPOSE: To determine if caffeine ingestion improves sprint performance in a dose-response manner. METHODS: Eight trained cyclists (VO2max = 54 ± 7 mL·kg-1·min-1) received 0 (placebo), 1, 3, 6 or 9 mg of caffeine·kg-1 BW 1-hour before performing 65-min of high-intensity exercise (78% VO2max). Maximal anaerobic cycling power was assessed at 15-min intervals using all-out 4-s sprint test. Oxygen uptake (VO2) and heart rate (HR) were measured after 10 and 60-min of exercise. Statistics were performed using repeated measures ANOVA.FigureRESULTS: Caffeine improved maximal anaerobic cycling power (P < 0.05) as shown in Figure 1. The increase in VO2 between 10 and 60-min of exercise (i.e., metabolic drift) was reduced by caffeine ingestion (111 ± 40 vs -50 ± 42, -23 ± 23, -50 ± 53, -37 ± 27 mL for 0 vs 1, 3, 6 and 9 mg·kg-1, respectively; P < 0.05) while HR drift was unaffected (6 ± 6 beats·min-1 in all trials). CONCLUSIONS: Caffeine improved sprint performance in a dose-response manner; while 1 mg·kg-1 BW (∼ 1 cup of coffee or 1 can of cola) had marginal effects on sprint performance, 9 mg·kg-1 BW improved maximal power by 5%. In addition, caffeine reduced the metabolic drift produced during high-intensity exercise by increasing VO2 early in exercise.