Abstract

Extensive data on cardiac output (Q) at rest and during graded exercise suggests that the Q is quite stable for a given oxygen corsumption (VO2) for a wide variety of normal male subjects and that the relationship is independent of most methods used to measure. Q. Our purpose was to develop regression equations for the Q-VO2 relation for men when Q and VO2 were normalized for body weight and to determine the effect on the relationship of inter-subject and intrasubject variability, and of age, weight, and VO2 max of the subject. We found no significant difference between the intercepts or the slopes for the Q-VO2 relation calculated from data on different subjects or on the same subject. Furthermore, no signoficant difference was observed between intersubject variability. The slope of the Q-VO2 relation was not significantly different for men of different ages, weights, and VO2 max. The intercept of the normalized Q-VO2 relation was significantly lower for men over 40 years ofage with VO2max less than 30mlxkg-1xmin-1 than for young men or elderly men with higher VO2max. The difference in intercepts may be due to body fat in excess of 18. For normal men, the Q can be estimated with reasonable accuracy from the exercise VO2. Verf.-Referat