Influence of ingesting versus mouth rinsing a carbohydrate solution during a 1-h run

To investigate the influence of ingesting versus mouth rinsing a carbohydrate-electrolyte solution on 1-h running performance.

After a 14- to 15-h fast, 10 endurance-trained male runners (mean ± SD: VO2peak = 65.0 ± 4.4 mL·kg(-1)·min(-1)) completed three 1-h performance runs separated by 1 wk. In random order, runners ingested either a 8-mL·kg(-1) body mass of either a 6.4% carbohydrate-electrolyte solution (CHO) or a placebo solution (P) 30 min before or a 2-mL·kg(-1) body mass at 15-min intervals throughout the 1-h run. On a separate occasion, runners mouth rinsed (R) a 6.4% CHO, i.e., without ingestion, at the same times as in the ingestion trials.

Total distances covered in the CHO, P, and R trials were 14,515 ± 756, 14,190 ± 800, and 14,283 ± 758 m, respectively. Runners covered 320 m more (90% confidence interval = 140-510 m, P = 0.01) during the CHO trial compared with the P trial and 230 m more (90% confidence interval = 83-380 m, P = 0.019) in comparison with the R trial. There was no difference in n distance covered between the R and P trials (P = 1.0).

A greater distance was covered after the mouth rinse and ingestion of a 6.4% CHO during a 1-h performance run than when mouth rinsing the same solution or mouth rinsing followed by the ingestion of the same volume of a placebo solution.