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Updated: Mar 13, 2026

Assessing Energy Substrate Oxidation In Vitro with 14CO2 Trapping
Published on: March 23, 2022
Similar substrate oxidation rates in concentric and eccentric cycling matched for aerobic power output
Laurie Isacco1, Ophélie Ritter2,3, Nicolas Tordi2,4
1a EA 3920 and Exercise Performance Health Innovation Platform, Franche-Comté University, 25000 Besançon, France.
Abstract:
This study investigated substrate oxidation in concentric and eccentric cycling matched for aerobic power output in the postprandial state. Energy expenditure, respiratory exchange ratio, and fat and carbohydrate oxidation rates were measured at rest and after 15, 30, and 45 min of eccentric and concentric cycling in 12 men. Absolute and relative aerobic power output and energy expenditure were similar during concentric and eccentric exercise. No effect of exercise modality was observed for substrate metabolism.
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