We have done EEG tests on athletes and in unfit subjects aged between 18 and 23 in order to study endurance and changes in bioelectrical activity of the brain caused by local forearm muscular performance by means of an ergograph until fatigue set in. We have found that all the endurance parameters in both dynamical performance and static tensions were higher in the athletes than in the unfit subjects. As fatigue set in, an elevated spectral power of slow α- and θ- waves was detected in all of the subjects, but the changes in question set in later in the group of athletes and were less pronounced than in the group of unfit subjects and yielded synchronized α-waves and reduced low-frequency and high-frequency β-waves on the EEGs. We have concluded that the athletes, in contrast to the unfit subjects, have higher endurance and lower fatigability throughout local muscular performance, which is in accord with bioelectrical changes recorded in the EEG tests.