Cardiac output: is there a sex difference?

An analysis is presented which challenges the supposition that men, in general, have higher resting cardiac outputs than women. The basis of the challenge relies on the fact that the blood oxygen carrying capacity of women is generally below that of men, which should be an offsetting factor. To test this hypothesis, data was obtained from standard tables of normal physiological indices. Using this data, simple calculations were made which did indeed tend to support the belief that a true sex difference exists. However, other calculations were made using a different method which tended to refute this supposition.