Journal of Applied Physiology, Vol 45, Issue 1 60-63, Copyright © 1978 by American Physiological Society
Comparison of metabolic and ventilatory responses of men to various lifting tasks and bicycle ergometry
J. S. Petrofsky and A. R. Lind
Four male volunteers served as subjects to examine the metabolic and
ventilatory cost of both positive and negative lifting tasks as compared to
bicycle ergometry. In different experiments, four boxes weighing 0.91,
6.82, 22.73, and 36.36 kg were lifted up to or down from a height of 60 cm
at rates as high as 70 lifts/min for periods of 4 min. The data were then
compared to those obtained from bicycling at a rate of 50 rpm at work loads
up to 1,500 kmp/min. Work at any given box weight had a substantially
higher oxygen and ventilatory cost than similar levels of work on the
bicycle ergometer. The reason for these differences appeared to lie in the
energy cost of moving parts of the body. When the weight of the boxes was
low, there was little difference between the oxygen cost of positive and
negative work, but as the weight of the boxes increased, the expected
physiological differences in positive and negative work was established.
