Effects of periodization of carbohydrate intake on performance and energy metabolism in the trained subject

High-level endurance performance is conditioned by training volume and the implementation of adaptive phenomena. Acute changes in carbohydrate availability modify the immediate response to exercise, and influence muscle adaptation processes in the trained subject when repeated over days or weeks. Recent studies have shown that training programs in which part of the work is performed with low muscle glycogen reserves and/or low exogenous carbohydrate intakes can increase the adaptive response to training through an increase in the peak activities of certain enzymes involved in carbohydrate and/or lipid metabolism, and a stimulation of mitochondrial biogenesis.

The aim of this study, carried out by three laboratories belonging to Carnot STAR, is to characterize the evolution of performance (40km cycling time trial) and the adaptive response of this carbohydrate periodization strategy by analyzing the time course of energy metabolism adaptations: measurement of muscle glycogen content by MRI, expression levels of the genes involved and biological functions, monitoring of energy metabolism.