Reoxygenation rate immediately after static short-term high intensity exercise indicates muscle oxidative capacity

The purpose of this study was to determine whether the reoxygenation rate (Reoxy-rate) immediately after static exercise at various submaximal intensities could indicate the muscle oxidative capacity. Seven healthy male subjects performed a static hand grip exercise for 10 seconds at 30%, 60% and 90% MVC. The Reoxy-rate was monitored by near infrared spectroscopy (NIRS). The muscle oxidative capacity was evaluated by the time constant (Tc) of the phosphocreatine (PCr) resynthesis rate by using 31-phosphorus magnetic resonance spectroscopy (31P-MRS). There was no correlation between the muscle oxidative capacity and Reoxy-rate at 30% and 60% MVC. However, the Reoxy-rate at 90% MVC was significantly correlated to the muscle oxidative capacity (r=0.825, p<0.05). In conclusion, in the case of static short-term contraction at 90% MVC, the Reoxy-rate after exercise is an indicator of the muscle oxidative capacity. However, Reoxy-rate may not be correlated to muscle oxidative capacity at 60%MVC and lower.

Duke Scholars

Author Takuya Osada Surgery, Surgical Sciences