Journal of Applied Physiology, Vol 55, Issue 2 440-446, Copyright © 1983 by American Physiological Society
Breathing patterns during submaximal and maximal exercise in elite oarsmen
J. M. Clark, F. C. Hagerman and R. Gelfand
Continuous breath-by-breath measurements of ventilatory parameters were
performed during submaximal and maximal treadmill exercise in 21 highly
conditioned oarsmen. Average maximum values of O2 uptake, minute
ventilation (VI), tidal volume (VT), and respiratory frequency (f) were
6.60 l/min (73.5 ml X kg-1 X min-1), 200 l/min, 3.29 l, and 62 breaths/min,
respectively. During the transition from moderate to heavy submaximal
exercise, VT and f increased progressively. At near-maximal to maximal work
loads, VT plateaued and then decreased slightly, while f continued to
increase. Increase in f at the start of exercise was achieved predominantly
by an abrupt decrease in expiratory duration (TE) with an equally abrupt,
but much smaller, decrease in inspiratory duration (TI). During the
transition from submaximal to maximal exercise, both TE and TI decreased
progressively. Although f appeared to be entrained by stepping rate in a
few subjects, the dominant trend during submaximal to maximal exercise was
characterized by a relatively small increase in stepping rate with a much
larger increment in f. Our data are consistent with the conclusion that
exercise breathing patterns are determined by many interacting factors that
vary at different work loads, in different individuals, and are probably
also influenced by physical conditioning and previous experience.
