Effects of carbohydrate-hydration strategies on glucose metabolism, sprint performance and hydration during a soccer match simulation in recreational players.
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.
['Kingsley|Michael|M|', 'Penas-Ruiz|Carlos|C|', 'Terry|Chris|C|', 'Russell|Mark|M|']
D000328:Adult D054874:Athletic Performance D001628:Beverages D001786:Blood Glucose D002110:Caffeine D018592:Cross-Over Studies D004040:Dietary Carbohydrates D019587:Dietary Supplements D004311:Double-Blind Method D004573:Electrolytes D006801:Humans D009994:Osmolar Concentration D005082:Physical Exertion D012420:Running D012916:Soccer D012964:Sodium D055815:Young Adult
Supplementation Football Rebound hypoglycemia Shooting