Accuracy Of Perceived Exertion In Older Adults Performing Common Daily Tasks

To examine the relationship between ratings of perceived exertion (RPE) and metabolic effort in older adults performing common daily tasks. Though metabolic responses to physical activity explain the majority of RPE variance among young adults, few studies have evaluated whether metabolic effort is associated with RPE in older adults. Forty-five community-dwelling older adults (70-90 years) performed 14 daily tasks in a laboratory setting at a self-selected pace. During testing, participants wore a portable metabolic unit to measure pulmonary gas exchange. Metabolic equivalents (MET) were calculated as ventilation of oxygen (VO sub(2)) / 3.5 mlkg super(-1)min super(-1). Correlational analysis revealed a significant but weak association between RPE and METs (R super(2) = 0.07, p < 0.01), indicating that physiological responses to physical activity only explains 7% of the variance in perceived exertion among older adults. Analyses to establish the directionality of the error revealed that of the 38% of participants demonstrating exertional error, 21% overestimated and 17% underestimated moderate/vigorous intensity exertion (>3 METs).