[The Effect of Cognitive Load on the Development of Muscle Fatigue]

The aim of our study was to examine the effect of cognitive load on the development of muscle fatigue. Sub- jects performed 250 maximal compressions of a handgrip dynamometer in response to the target acoustic stimulus. Stimuli were presented in three paradigms with different levels of cognitive load: (1) the reaction task with one type of signals (2) the acoustic stimuli recognition task with the 50% target and 50% non-target stimuli, where voluntary attention was involved, (3) the recognition task with the 17% target and 83% non tar- get stimuli, that led to the activation of voluntary and involuntary attention systems. As fatigue indicators amplitude of compression force in response to the target stimulus, the maximum voluntary contraction and rating of perceived exertion were used. Our results showed the reduced level of fatigue in experiment with the activation of voluntary and involuntary attention systems. Moreover, the activation of involuntary attention, accompanied by mismatch negativity in the EEG, enhanced the effect of voluntary attention.