Purpose: To investigate the effect of ingesting a carbohydrate-electrolyte solution (CHO-E), in subjects with reduced carbohydrate stores, during an intermittent shuttle running test (LIST) on soccer passing (LSPT) and shooting (LSST) performance.
Methods: Sixteen healthy male university soccer players ingested either a 6.4% CHO-E or placebo (PLA) solution during 90 min of the LIST (5 mL·kg−1 BM before and 2 mL·kg−1 BM every 15 min of exercise), in a double-blind, randomized, crossover design, with each trial separated by at least 7 d. On the evening before the main trial (17:00 h), subjects performed the glycogen-reducing cycling exercise (~80 min at 70% V˙O2max). They were then fed a low-carbohydrate evening meal and reported to the laboratory the following morning after a 10-h fast. Blood was collected at rest and after every 30 min of exercise; skill tests were performed before and after the LIST.
Results: The change in mean LSST performance from pre- to post-LIST was better in the CHO-E trial (11 ± 45 vs −16 ± 42%; P < 0.01) but not significantly different for the LSPT performance (−1 ± 10% (CHO-E) vs −6 ± 13% (PLA), P = 0.13). Sprint performance during the LIST was quicker in the CHO-E trial (2.50 ± 0.13 vs 2.53 ± 0.13 s, P < 0.01). Plasma glucose was higher in the CHO-E trial after 90 min of exercise (5.2 ± 0.3 vs 3.9 ± 0.4 mM, P < 0.01).
Conclusions: Ingestion of a carbohydrate-electrolyte solution during exercise enabled subjects with compromised glycogen stores to better maintain skill and sprint performance than when ingesting fluid alone.