Phosphocreatine recovery in the human tibialis anterior after dynamic exercise shows a proximo-distal gradient, which is not explained by acetylcarnitine differences.

The phosphocreatine (PCr) recovery rate of the tibialis anterior muscle after isometric exercise shows a strong gradient along the length of the muscle. In this study we demonstrate that this also holds for dynamic exercise of the TA. To further examine if mitochondrial metabolism is involved we determined acetylcarnitine (AC) levels along the length of the TA, but no differences were detected. Together with previous correlations found for blood oxygenation by NIRS experiments and perfusion by IVIM we conclude that muscle perfusion and oxygenation are main components determining the PCr recovery gradient in the TA.