Mears_CHO_pattern_MSSE_v3_accepted.pdf (4.96 MB)
Sports drink intake pattern affects exogenous carbohydrate oxidation during running
journal contribution
posted on 2020-03-30, 12:09 authored by Stephen MearsStephen Mears, Benjamin Boxer, David Sheldon, Hannah Wardley, Caroline A Tarnowski, Lewis JamesLewis James, Carl HulstonPURPOSE: To determine whether the pattern of carbohydrate sports drink ingestion during prolonged sub-maximal running affects exogenous carbohydrate oxidation rates and gastrointestinal (GI) comfort. METHODS: Twelve well-trained male runners (27 ± 7 y, 67.9 ± 6.7 kg, V[Combining Dot Above]O2peak: 68 ± 7 mL·kg·min) completed two exercise trials of 100 min steady state running at 70% V[Combining Dot Above]O2peak. In each of the trials, 1 L of a 10% dextrose solution, enriched with [U-C] glucose, was consumed as either 200 mL every 20 min (CHO-20) or 50 mL every 5 min (CHO-5). Expired breath and venous blood samples were collected at rest and every 20 min during exercise. Subjective scales of GI comfort were recorded at regular intervals. RESULTS: Average exogenous carbohydrate oxidation rates were 23% higher during exercise in CHO-20 (0.38 ± 0.11 vs. 0.31 ± 0.11 g·min; P=0.017). Peak exogenous carbohydrate oxidation was also higher in CHO-20 (0.68 ± 0.14 g·min vs. 0.61 ± 0.14 g·min; P=0.004). During exercise, total carbohydrate oxidation (CHO-20: 2.15 ± 0.47; CHO-5: 2.23 ± 0.45 g·min, P=0.412) and endogenous carbohydrate oxidation (CHO-20: 1.78 ± 0.45; CHO-5: 1.92 ± 0.40 g·min; P=0.148) were not different between trials. Average serum glucose (P=0.952) and insulin (P=0.373) concentrations were not different between trials. There were no differences in reported symptoms of GI comfort and stomach bloatedness (P>0.05), with only 3% of reported scores classed as severe (>5 out of 10). CONCLUSION: Ingestion of a larger volume of carbohydrate solution at less frequent intervals during prolonged submaximal running increased exogenous carbohydrate oxidation rates. Neither drinking pattern resulted in increased markers of GI discomfort to a severe level.
History
School
- Sport, Exercise and Health Sciences
Published in
Medicine and Science in Sports and ExerciseVolume
52Issue
9Pages
1976 - 1982Publisher
Lippincott, Williams & WilkinsVersion
- AM (Accepted Manuscript)
Rights holder
© American College of Sports MedicinePublisher statement
This is a non-final version of an article published in final form in MEARS, S. ... et al, 2020. Sports drink intake pattern affects exogenous carbohydrate oxidation during running. Medicine and Science in Sports and Exercise, 52 (9), pp.1976-1982, doi: 10.1249/MSS.0000000000002334.Acceptance date
2020-02-27Publication date
2020-03-10Copyright date
2020ISSN
0195-9131eISSN
1530-0315Publisher version
Language
- en