Effect of caffeine ingestion after creatine supplementation on intermittent high-intensity sprint performance

Abstract

The aim of this study was to investigate the effects of acute caffeineingestion on intermittent highintensity sprint performance after 5 days of creatine loading. After completing a control trial (no ergogenic aids, CON), twelve physically active men were administered in a double-blind, randomized crossover protocol to receive CRE + PLA (0.3 g kg -1day-1 of creatine for 5 days then followed by 6 mg kg -1 of placebo)and CRE + CAF (0.3 gkg -1 day-1 of creatine for 5 days and followed by 6 mg kg -1 of caffeine), after which theyperformed a repeated sprint test. Each test consisted of six 10-s intermittent high-intensity sprints on a cycling ergometer, with 60-srest intervals between sprints. Mean power, peak power, rating of perceived exertion (RPE), and heart rates were measured during the test. Blood samples for lactate, glucose, and catecholamine concentrations were drawn at specified intervals. The mean and peak powerobserved in the CRE + CAF were significantly higher than those found in the CON during Sprints 1 and 3; and the CRE + CAF showed significantly higher mean and peak power than that in the CRE + PLA during Sprints 1 and 2.Themean and peak power during Sprint 3 in the CRE + PLA was significantly greater than that in the CON. Heart rates, plasma lactate, and glucose increased significantly with CRE + CAF during most sprints. No significant differences werez observed in the RPE among the three trials. The present study determined that caffeine ingestion after creatine supplements augmented intermittent high-intensity sprint performance. © Springer-Verlag 2011.