Comparison of some physiological indices during paced and unpaced work

SUMMARY

Trained subjects performed a simple assembly task under self-paced and machine-paced working conditions. Work cycle times, respiratory intervals and cardiac R—R intervals were recorded continuously throughout 2 hours of unpaced and 2 hours of paced work of the same rate as the subject's mean unpaced performance. The two kinds of work were shown to be physiologically different, not in the direction physiological changes, but in their general levels and rates of change. The results indicated that the unpaced work imposed a higher load upon the subject than the paced work. It is also indicated that the organism may be prepared in advance for the work under unpaced conditions, while it seems to be ‘driven’ by the machine under paced conditions, and works with a kind of momentary ‘physiological lag’.