Training-induced changes on quadriceps muscle oxygenation measured by near-infrared spectroscopy in healthy subjects and in chronic obstructive pulmonary disease patients.

Endurance training further decreased StO2 during CWRE, similarly in both groups, likely due to training-induced enhancement of muscle O2 transfer and utilization. Training-induced StO2 fall during CWRE may be useful individual marker for non-invasive assessment of enhanced muscle aerobic post-training function.