title: Cardiac output differences in males and females during mild cycle ergometer exercise.
abstract: To study sex differences in cardiac output during submaximum exercise, eight male and eight female subjects were matched on max Vo2 (1 min-1 and ml kg-1 min-1). Each subject performed one, eight minute submaximum bicycle ergometer test at 35% of Vo2max (300 kpm min-1). At a steady state mean Vo2 of 0.96 1 min-1, cardiac output was determined. Significant differences between men and women were observed (p less than .05) in cardiac output, stroke volume and (a-v) O2 difference. The males had a lower cardiac output (1.75 1 min-1) and stroke volume (17.2 ml beat-1) and a higher (a-v) O2 difference (2.01 vol %). When these variables were expressed independent of lean body weight the above differences were non-significant. It was suggested that cardiac output differences between the sexes during mild exercise are due, in part, to differences in lean body weight.
mesh_terms: D000328:Adult; D002302:Cardiac Output; D005260:Female; D006801:Humans; D008297:Male; D005082:Physical Exertion; D012737:Sex Factors