Fatigue Effects on the Timing Performance of Well-Practiced Subjects

Abstract

In an attempt to extend the laws of fatigue to the performance of highly practiced subjects, 24 college males were trained for four days (50 trials/day) on a coincident timing task prior to manipulation of the fatigue variable. On day 5, motor performance was immediately preceded by either local fatigue (static exercise), general fatigue (treadmill running), or no fatigue. Increased variable error was found for both local and general fatigue subjects as compared with controls on the first block of five trials following fatigue. However, by block 2 this difference had diminished. A constant error analysis on the first and second postfatigue trials revealed transitory overshooting of the criterion timing response for local fatigue subjects and undershooting for general fatigue subjects. The results suggested that local and general fatigue may alter the timing mechanism in different ways and that both are sources of at least transient decrements in the performance of well-practiced subjects.