Target heart rates for the development of cardiorespiratory fitness

The American College of Sports Medicine (ACSM) recommends the use of 40%, 60%, 80%, and 85% of maximal oxygen consumption (VO2max) as target values in developing exercise prescriptions. Further, the ACSM states that 55%, 70%, 85%, and 90% of maximal heart rate (HRmax) may be used as indices of these respective levels of % VO2max for the general population. The current study evaluated this relationship between %HRmax and %VO2max in apparently healthy, young adults. Eighty-one men and 81 women between the ages of 18 and 34 engaged in an incremental exercise test to exhaustion. Linear regressions of %HRmax and %VO2max were performed on each subject. From these regressions, target values of %HRmax were computed for each individual. Mean percentages of HRmax were 63%, 76%, 89%, and 92% at 40%, 60%, 80%, and 85% of VO2max, respectively. At all of these values of %VO2max, the values obtained for %HRmax were significantly greater (P < 0.001) than those used by the ACSM. Fitness affected these results, particularly among men. High fit men averaged 2% higher in %HRmax than low fit men at any given value of %VO2max.