A critical evaluation of current methods for exercise prescription in women and men

Common methods to prescribe exercise intensity are based on fixed-percentages of maximum rate of oxygen uptake (V[Combining Dot Above]O2max), peak work rate (WRpeak), maximal heart rate (HRmax). However, it is unknown how these methods compare to the current models to partition the exercise intensity spectrum. PURPOSE: Thus, the aim of this study was to compare contemporary gold-standard approaches for exercise prescription based on fixed-percentages of maximum values to the well established but underutilized "domain" schema of exercise intensity. METHODS: One hundred individuals participated in the study (women=46; men=54). A cardiopulmonary ramp-incremental test was performed to assess V[Combining Dot Above]O2max, WRpeak, HRmax, and the lactate threshold (LT), and submaximal constant-work rate trials of 30-min duration to determine the maximal lactate steady-state (MLSS). The LT and MLSS were used to partition the intensity spectrum for each individual in three domains of intensity: moderate, heavy, and severe. RESULTS: V[Combining Dot Above]O2max in women and men was 3.06±0.41 L·min and 4.10±0.56 L·min, respectively. LT and MLSS occurred at a greater %V[Combining Dot Above]O2max and %HRmax in women compared to men (P<0.05). The large ranges in both sexes at which LT and MLSS occurred on the basis of %V[Combining Dot Above]O2max (LT=45-74%; MLSS=69-96%), %WRpeak (LT=23-57%; MLSS=44-71%), and %HRmax (LT=60-90%; MLSS=75-97%) elicited large variability in the number of individuals distributed in each domain at the fixed-percentages examined. CONCLUSIONS: Contemporary gold-standard methods for exercise prescription based on fixed-percentages of maximum values conform poorly to exercise intensity domains and thus do not adequately control the metabolic stimulus.