Relationship between Muscle Oxygenation Kinetics and Tolerance to Fatigue on Short-term Isometric Knee Extension Exercise

Abstract

The purpose of this study was to examine the relationship between muscle oxygenation kinetics and tolerance to fatigue (Fr) on short-term maximal isometric knee extension exercise for healthy endurance-trained women. The decline rate of Tissue Oxygenation Index (TOI) at the onset of exercise had a significant negative correlation to Fr (r=-0.76, p<0.05). The half-time of TOI recovery tended to have a positive correlation to Fr (r=0.74, p=0.056). The subjects with higher localized tolerance to fatigue showed greater deoxygenation at the onset of exercise and faster reoxygenation at recovery.