The Cycling Endurance Study
Probiotic supplementation increases carbohydrate metabolism in trained male cyclists: a randomised, double-blind, placebo-controlled cross-over trial
Aim
This randomised, double-blind, placebo controlled study aimed to assess whether Lab4 probiotic supplementation increases the absorption and oxidation of orally ingested maltodextrin and total carbohydrates oxidation during 2 hours endurance cycling.
Method
- The study was carried out at the Research Institute for Sport and Exercise Sciences, Liverpool John Moores University.
- Seven trained male cyclists (age 23 ± 4 years) were divided into two groups.
Group 1 took one placebo capsule daily for 28 days.
Group 2 received one capsule of 25 billion Lab4 probiotics daily for 28 days.
- After 28 days of supplementation, the volunteers took their additional supplement dose on the morning of the trial (1 h before exercise) and underwent 2 h of cycling at 55% Wmax (maximal workload), followed by a 100-kJ time trial (simulating the final sprint in a competitive, long distance road race).
During exercise participants consumed 180 g of 10% carbohydrate drink (maltodextrin and labelled glucose).
- Following a 14-day washout period, the cyclists who took a placebo in the first 28 days received Lab4 probiotics and vice versa. After 28 days of supplementation and an additional supplement dose prior trial, the volunteers repeated the same cycling exercise.
- The parameters investigated were the carbohydrate and fat oxidation, plasma metabolites and gut disturbance.
Results
Carbohydrate oxidation
- Significant increase in carbohydrate (CHO) oxidation in the Lab4 probiotic group compared to placebo (*P<05).
Fat oxidation
Plasma Glucose
Plasma Insulin
Gut Symptoms
- The incidence of gastrointestinal symptoms during cycling exercise was low in both groups, suggesting that the intensity and duration of the exercise did not lead to significant gut disturbance.
Conclusion
Lab4 probiotics supplementation increases total carbohydrate oxidation, whereas fat oxidation was reduced during the endurance cycling.
Reference
Pugh JN et al 2020. Probiotic supplementation increases carbohydrate metabolism in trained male cyclists: a randomised, double-blind, placebo-controlled crossover trial. American Journal of Physiology, Endocrinology and Metabolism 318 (4): E504-E513