Sex-specific differences in cervical muscle fatigue during sustained non-neutral exertions

Given the contribution of sustained neck exertion in non-neutral postures to the prevalence of neck pain in the workplace, the sex-specific fatigability rates of neck muscles were investigated using an integrated analysis of electromyography (EMG) median frequency (MF) and EMG Amplitude-Force ratio. The EMG MF and EMG Amplitude-Force ratio data of 18 males and 19 females were analyzed using piecewise linear regression models. The results showed that the time- and sex-specific fatigability rates are task- and muscle-dependent, with tasks relying primarily on the smaller muscles in the force production incurred a more significant amount of muscle fatigue for males than females.