Lab 13: Physical Working Capacity at the Heart Rate Threshold (PWCHRT) Test

Theoretically, the physical working capacity at the heart rate threshold (PWC_HRT) test provides an estimate of the maximal power output during cycle ergometry that can be maintained for a very long period of time (four to eight hours) with no increase in heart rate (e.g., a steady-state heart rate). ^1,2 The PWC_HRT test is most applicable to situations where assessing the ability to perform long-term, submaximal physical activity is more important than defining a subject’s maximal exercise capacity (such as maximal oxygen consumption rate, VO₂ max). Potential applications of the PWC_HRT test include assessing the physical working capacity of workers in industrial settings where strenuous labor is performed for eight or more hours per day, evaluating the effectiveness of endurance-training programs in a variety of populations including the elderly, and examining the training status of ultraendurance athletes such as triathletes or long-distance cyclists. ^1,3 Furthermore, the submaximal protocol used to determine the PWC_HRT makes it appropriate for assessing aerobic fitness in subjects where maximal exercise testing may be contraindicated, such as the elderly or clinical populations.