Rapid regulation of substrate use for oxidative phosphorylation during a single session of high intensity interval or aerobic exercises in different rat skeletal muscles.

Different exercise protocols lead to long-term adaptations that are related to increased mitochondrial content through the activation of mitochondrial biogenesis. However, immediate mitochondrial response to exercise and energetic substrate utilization is still unknown. We evaluate the mitochondrial physiology of two types rat skeletal muscle fibres immediately after a single session of high intensity interval exercise (HIIE) or aerobic exercise (AER).