Effects of carbohydrate-hydration strategies on glucose metabolism, sprint performance and hydration during a soccer match simulation in recreational players

摘要

Objectives: This study compared the effects of three carbohydrate-hydration strategies on blood glucose concentration, exercise performance and hydration status throughout simulated soccer match-play. Design: A randomized, double-blind and cross-over study design was employed. Methods: After familiarization, 14 recreational soccer players completed the soccer match simulation on three separate occasions. Participants consumed equal volumes of 9.6% carbohydrate-caffeine-electrolyte (~6. mg/kg BW caffeine) solution with carbohydrate-electrolyte gels (H-CHO), 5.6% carbohydrate-electrolyte solution with electrolyte gels (CHO) or electrolyte solution and electrolyte gels (PL). Blood samples were taken at rest, immediately before exercise and every 15. min during exercise (first half: 15, 30, 45. min; second half: 60, 75, 90. min). Results: Supplementation influenced blood glucose concentration (time. ×. treatment interaction: p<. 0.001); however, none of the supplementation regimes were effective in preventing a drop in blood glucose at 60. min. Mean sprint speed was 3. ±. 1% faster in H-CHO when compared with PL (treatment: p=. 0.047). Supplementation caused a 2.3. ±. 0.5% increase in plasma osmolality in H-CHO (p<0.001) without change in CHO or PL. Similarly, mean sodium concentrations were 2.1. ±. 0.4% higher in H-CHO when compared with PL (p=0.006). Conclusions: Combining high carbohydrate availability with caffeine resulted in improved sprint performance and elevated blood glucose concentrations throughout the first half and at 90. min of exercise; however, this supplementation strategy negatively influenced hydration status when compared with 5.6% carbohydrate-electrolyte and electrolyte solutions.