HUMAN CARDIOPULMONARY RESPONSES TO EXERCISE - COMPARISONS BETWEEN PROGRESSIVE AND STEADY STATE EXERCISE BETWEEN ARM AND LEG EXERCISE AND BETWEEN SUBJECTS DIFFERING IN BODY WEIGHT

The regressions of the oxygen uptake on rate of work, of the ventilation and cardiac frequency on oxygen uptake, and of the ventilation on tidal volume have been obtained over the ranges where they were linear during pedalling and during cranking a cycle ergometer. The regression coefficients for ventilation and cardiac frequency on oxygen uptake are higher for light than for heavy subjects, and for work which is performed with the arms instead of the legs; possible reasons are discussed. The respiratory frequency in relation to tidal volume is also higher for arm than for leg work. In the comparison of progressive and steady state exercise no systematic differences were observed, except for the relationship of the consumption of oxygen to the rate of work; this finding is relevant to the planning of exercise studies on normal subjects. © 1969 The Physiological Society