Muscle oxygenation correlates of handgrip fatigue with obesity

The aims of this study were to determine obesity-related muscle oxygenation correlates of submaximal fatigue, across 20, 40, 60, and 80% of maximum voluntary contractions (MVC). 72 normal weight, overweight and obese adults, matched by gender, performed the four endurance tests on different days. Muscle oxygenation of the flexor and extensor carpi radialis were measured by near infrared spectroscopy and endurance time was recorded for each test. The findings indicated that obesity-related reduction in handgrip endurance was evident at low force contraction levels. Obesity was associated with impaired muscle oxygenation; however, the changes were independent of force contraction levels. Muscle oxygenation did not directly limit the time to failure for endurance tests at higher force levels. Thus, it is likely that factors other than local metabolic and hemodynamic changes impede fatigue resistance at higher force contraction levels.