Approximate normal standards of maximal cardiac output during upright exercise in women.

The observed normal ranges of age- and weight-adjusted maximal oxygen uptake and age-adjusted maximal heart rate during upright exercise using the Bruce protocol are shown for 104 asymptomatic women. Cardiac output was measured during upright exercise in 11 normal women with the use of the direct Fick method. On the basis of the relation between oxygen uptake and cardiac output in these 11 women, the cardiac output and stroke volume were estimated by regression in the 104 women to provide normal ranges of age-adjusted values for cardiac output and stroke volume. The potential usefulness of these age-adjusted normal ranges is illustrated by analysis of 21 observations of maximal cardiac output in 16 women with heart disease.