Effects of an active halftime rewarm-up, with carbohydrate supplementation, on player's blood glucose and second half performance during a collegiate soccer match

Abstract

BACKGROUND: The half-time (HT) period of a soccer match is viewed as a period for recovery. Completely inactive and passive HT has implications on metabolic responses and subsequent performance during the initial phases of the second half. PURPOSE: Determine the effects of an active rewarm-up, compared to a passive period, at halftime on various measures of performance during the first 15-minutes of the second half using global positioning system (GPS) units. Identify the effects of the active versus passive HT period, with CHO beverage supplementation, on blood parameters. METHODS: Crossover design study, twenty collegiate male soccer players participated in two 90-minute soccer matches with passive rest (CON) or a moderate-intensity rewarm-up (RWU) during HT with CHO supplementation. Subjects received five fingerstick blood samples throughout the match (BG) and four subjects had serum insulin/BG taken three times during the match. RESULTS: RWU had significantly (p<0.05) higher measures for total distance, average speed, speed exertion, accelerations, HMP distance, decelerations, and EE during TI-4 half when compared to CON. No subjects experienced hypoglycemia. However, CON did have a significant drop in BG after HT and the lowest mean BG taken at 60-minutes. Tendency for CON and RWU to have HT insulin levels that were elevated and reduced, respectively. CONCLUSION: A passive HT period is not optimal, given its causal role in temporary physical performance deficits in the second half of soccer matches. The results provide a strong rationale for collegiate soccer players and teams to incorporate the 8-minute RWU into the HT regime to optimize second half performance.