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Updated: Jul 6, 2026
09:20
Assessing Energy Substrate Oxidation In Vitro with 14CO2 Trapping
Published on: March 23, 2022
Increased carbohydrate oxidation after ingesting carbohydrate with added protein.
James A Betts1, Clyde Williams, Les Boobis
1Sport and Exercise Science, University of Bath, Bath, United Kingdom. J.Betts@bath.ac.uk
Medicine and Science in Sports and Exercise
|April 15, 2008
Summary
Adding protein to carbohydrate supplements after exercise enhances the body's use of external carbohydrates during subsequent activity. This strategy improves whole-body carbohydrate oxidation without affecting muscle glycogen stores.
Area of Science:
- Exercise Physiology
- Sports Nutrition
- Metabolic Research
Background:
- Optimizing recovery nutrition is crucial for athletes undergoing multiple training sessions within a single day.
- Understanding the metabolic effects of nutrient timing and composition post-exercise informs performance enhancement strategies.
Purpose of the Study:
- To investigate the metabolic impact of incorporating protein into a postexercise carbohydrate supplement.
- To assess the effects on muscle glycogen resynthesis and subsequent exercise carbohydrate utilization.
Main Methods:
- Six healthy males completed two trials involving prolonged running, recovery, and a second run.
- Participants consumed either carbohydrate (CHO) or carbohydrate-plus-protein (CHO-PRO) supplements during recovery.
- Muscle biopsies and metabolic measurements were taken throughout the protocol.
Main Results:
- Muscle glycogen resynthesis rates were similar between CHO and CHO-PRO treatments.
- Muscle glycogen degradation during the second run was not significantly different between groups.
- Whole-body carbohydrate oxidation during the second run was significantly higher in the CHO-PRO group.
Conclusions:
- Including protein with carbohydrate supplements post-exercise enhances the utilization of non-muscle carbohydrate sources during subsequent exercise.
- This nutritional strategy can increase whole-body carbohydrate oxidation without compromising muscle glycogen replenishment.
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