Influence of ingesting a carbohydrate-electrolyte solution before and during a 1-hr running performance test.
The aim of this study was to investigate the influence of ingesting a carbohydrate-electrolyte solution (CHO-E) on performance during a 1-hr treadmill run. Eight male endurance-trained runners (age 31 +/- 8 yr, M +/- SD) completed three 1-hr performance runs separated by 1 wk. The study used a double-blind placebo (PLA) controlled design. On 2 occasions (P1, P2) runners consumed a placebo solution, 8 ml/kg body mass (BM), 30 min before and 2 ml/kg BM at 15-min intervals throughout the 1-hr run. On a separate occasion they consumed the same quantity of a 6.4% CHO-E solution (C). Total distances covered for P1, P2, and C trials were 13,685 +/- 1,116 m, 13,715 +/- 1,143 m, and 14,046 +/- 1,104 m, respectively. Although there was no difference between the 2 PLA trials (p > .05), the distance covered during the C trial was significantly greater than in either PLA trial (p < .05). CHO ingestion resulted in a higher blood glucose concentration only at the onset of exercise (p < .05) compared with the PLA trials. Blood lactate, respiratory-exchange ratio, and CHO oxidation were similar in all 3 trials. In conclusion, ingestion of a 6.4% CHO-E solution before and during exercise was associated with improved running performance in runners compared with the ingestion of a color- and taste-matched placebo.
Rollo
Ian
I
School of Sport and Exercise Sciences, Loughborough University, Loughborough, UK.
Williams
Clyde
C
D000328:Adult; D019540:Area Under Curve; D001786:Blood Glucose / Q000378:metabolism; D018592:Cross-Over Studies; D004040:Dietary Carbohydrates / Q000378:metabolism*; D004311:Double-Blind Method; D004326:Drinking / Q000502:physiology; D004573:Electrolytes / Q000008:administration & dosage* / Q000378:metabolism*; D006801:Humans; D019344:Lactic Acid / Q000097:blood; D008297:Male; D010807:Physical Endurance / Q000187:drug effects* / Q000502:physiology; D015532:Rehydration Solutions / Q000008:administration & dosage; D012420:Running / Q000502:physiology*; D013647:Task Performance and Analysis; D013997:Time Factors; D014882:Water-Electrolyte Balance / Q000502:physiology
D001786:Blood Glucose; D004040:Dietary Carbohydrates; D004573:Electrolytes; D015532:Rehydration Solutions; D019344:Lactic Acid