Relationship between heart rate and relative oxygen intake in male subjects aged 10 to 27 years

Regression equations relating heart rate (fh) to relative oxygen intake (% VO2max) have been calculated for bicycle ergometer exercise. The five groups of subjects were boys aged 10--11, 13--14 and 16--17 years, average young adults aged 23--27 years, and middle and long distance runners aged 20--25 years. The heart rate at a given % of VO2max was higher for younger than for older boys; however, the heart rate discrepancy between groups diminished at increasing intensities of exercise. The results are discussed in relation to the use of heart rates in training and exercise prescription. At high work loads, graphs of % maximum heart rate against % VO2max are relatively independent of age, but at the lower levels of activity common in everyday life, the % VO2max of adolescents must be predicted for age-specific regression lines.