CAFFEINE SUPPLEMENTATION IN TEAM SPORTS ATHLETES: SYSTEMATIC REVIEW AND META-ANALYSIS

Abstract

Caffeine (CAF) is a substance with stimulating properties, widely used by athletes. However, its effectiveness in competitive environments, particularly in team sports, remains unclear, as most studies in this area have employed laboratory tests. Therefore, the aim of the present study was to analyze the effects of CAF supplementation on game performance (in simulated and official matches) and vertical jump in team sports. A systematic review followed by a meta-analysis was conducted between May and June 2019 using the databases PubMed/MEDLINE, EMBASE, Web of Science, and SPORTDiscus. A total of 6,485 records were identified based on the keywords used. Twenty-one studies were included in the
systematic review, and 19 were included in the meta-analysis. A significant effect was observed in favor of CAF for: 1) the total distance covered during game simulations (Glass’s Δ = 0.44; 95% CI = 0.17–0.70; p < 0.01), 2) the number of sprints performed during simulated matches (Glass’s Δ = 0.33; 95% CI = 0.06–0.59; p = 0.02), and vertical jump height (Glass’s Δ =
0.25; 95% CI = 0.09–0.41; p = 0.02). The mean height of consecutive vertical jumps after CAF consumption showed an increase, with a small effect size (Glass’s Δ = 0.27; 95% CI = -0.04–0.57; p = 0.08). The combined effect of vertical jumps and consecutive vertical jumps demonstrated improvement following CAF (Glass’s Δ = 0.25; 95% CI = 0.11–0.39; p = 0.0004). The results suggest that CAF supplementation is an effective nutritional strategy to enhance athletic performance in specific tasks related to team sports. Well-controlled future studies with larger samples, exploring different team sports, varying levels of athlete performance, and other measures of game performance and attributes related to team sport performance, are necessary to advance knowledge in this area.