Citation

Manzer CW. J. Exp. Psychol. 1934; 17(2): 257-269.

Copyright

(Copyright © 1934, American Psychological Association)

DOI

10.1037/h0074799

PMID

unavailable

Abstract

27 college students performed a total of 297 work periods, in which the work of lifting a ten-pound weight with the flexors of the middle finger was continued to exhaustion. The following conclusions were drawn: Absolute variability decreases sharply in the early work periods of a series and fluctuates irregularly throughout the remainder of the series. Relative variability shows no regular change throughout the series. The work done with unfatigued muscles (first ten contractions) is more variable in the later periods of the series than in the earlier periods. With fatigued muscles (last ten contractions) there is no systematic change in variability throughout the series. A comparison of the work done in the first ten contractions of each work period with that done in the last ten contractions shows that the mean output of work done with fatigued muscles is one-fifth of that done with unfatigued muscles. The relative variability of work done with fatigued muscles is three times the variability of the work done with unfatigued muscles. (PsycINFO Database Record (c) 2012 APA, all rights reserved)