Glycogen-Depletion Has no Effect on Selected Marker of Skeletal Muscle Adaptation
In a recently published study, Camera et al. ( Camera. 2010 ) investigated the effect of isolated glycogen depletion on the rpS6 phosphorylation, a process which is closely related to the insulin/insulin-like growth factor (IGF) signalling pathway that is generally believed to be part of the positive adaptation processes of resistance exercise. By having their subjects perform a unilateral cycling exercise the evening before the test session, the scientists established a "divergent muscle glycogen content that was higher in the control leg (Norm) than in the Low leg at rest (383 ± 43 vs. 184 ± 14 mmol/kg dry wt; p < 0.05)". Thus, with the "normal" leg, they had an intra-(not inter-)individual reference for the results of the muscle biopsy after the testing protocol. Other than one might suspect, there was yet no difference between the rpS6 phosphorylation in the glycogen-depleted vs. the normal leg, which lead the scientists to conclude: These results indica...