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Relative exercise intensity refers to a portion of maximal power (load) that is maintained during exercise and is usually prescribed as a percentage of maximal aerobic capacity (VO2max) on the basis of a cardiopulmonary stress test. Training intensity can also be expressed as a percentage of maximal heart rate (HRmax) recorded in a stress test or predicted on the basis of an equation stating that HRmax equals 220 minus age.
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