Group Regressions Predicting Oxygen Consumption from Heart Rates in Japanese Male Adults

Abstract

The purpose of this paper is to evaluate errors among group regressions predicting oxygen consumption (Vo2) by heart rate (HR) method, and to obtain the fittest regression for each respective age groups and possibly a single regression for the entire subject population. Twenty male adults participated in the study and were divided into three age groups. Body height, weight, surface area (SA), lean body mass (LBM) and body cell mass (BCM) were determined by the standard anthropometry and the measurement of 40K by a whole body (human) counter. At the submaximal work test, and HR were calculated at 4 to 6 grades of work loads on a bicycle ergometer. All correlation coefficients of Vo2 to HR for groups were over 0.885 (p <0.001), while regression showed differences in slopes and intercepts between age groups. After correction applying indices of body composition and the ratio to resting HR (HRR), correlation coefficients of the old age group became greater, whereas correlation coefficients for the other two groups were almost unchanged when Vo2. were corrected by SA, LBM or BCM and related to HR. The age-difference in the group regressions disappeared in the relation between corrected by LBM and HR. Among ten sets of relation of corrected and HR (or HRR), only three indicated the age-difference clearly. These facts suggest the possibility of a single regression for all groups. Tentative regression equation for all the study-subjects showed the highest value of correlation coefficient, 0.936 (P<0.001) in case that Vo2 corrected by LBM or BCM was related to HRR. It was concluded that the group regression should be constructed by adopting HR (for young age groups) or HRR (for old age groups) with the correction of by SA, LBM or BCM (for both young and old age groups). We can use additionally body weight (for only old age groups); and that a single group regression, covering an age-range up to 50 years old, is possibly appUed in the relation between corrected Vo2 by LBM or BCM and HRR, with an error of about 25%. © 1982, Center for Academic Publications Japan. All rights reserved.