Factors Correlated with Rate of Perceived Exertion in Older Adults

Abstract

The rate of perceived exertion (RPE) is influenced by cardiopulmonary "signal mediators" such as heart rate, oxygen uptake, respiration rate, and minute ventilation, by peripheral mediators such as blood lactic acid concentration and blood pH, and by energy substrate availability, mechanical strain, skin and core temperature. Previous research has primarily focused on these physiological mediators, while little is known about the influence of subject's and exercise test characteristics on RPE. PURPOSE: We examined the correlation of subject's and exercise test characteristics with the Rate of Perceived Exertion (RPE) among older adults (>60 yrs). METHODS: We used data from men (N=57) and women (N=74) undergoing different types of exercise tests on a cycle ergometer: incremental tests (maximal and submaximal graded) and constant load tests in the heavy intensity domain (80, 85, and 95% of maximum work rate). Overall body RPE was assessed with the Borg (6 20) and OMNI scales (0 10). A multi step approach was used to build multivariate linear regression models including all the variables that significantly influenced the relationship between relative work capacity and RPE. RESULTS: Age was significantly correlated with Borg RPE and OMNI RPE both in men (regression coefficient 0.285, 95% confidence interval 0.433 - 0.083, and 0.051, 0.191 - 0.012, respectively), and women (0.568, 0.740 - 0.395, and 0.298, 0.499 - 0.147, respectively). Also, a significant correlation was found for variables related to subject's performance level: respiratory rate at ventilatory threshold among men (Borg RPE 0.085, 0.048 - 0.122; OMNI RPE 0.046, 0.017 - 0.075), and oxygen consumption among women (Borg RPE 1.061, 1.629 - 0.492; OMNI RPE 1.271, 0.255 - 0.123). The multivariate model for Borg RPE included the type of physical exercise training only for men (0.340, 0.472 - 0.209), while the model for OMNI RPE included it only for women (0.124, 0.026 - 0.223). Eventually, the rate of workload increase was significantly correlated with both Borg RPE and OMNI RPE in women: 0.194, 0.272 - 0.115, and 0.189, 0.255 - 0.123, respectively. CONCLUSIONS: RPE is correlated with age, with variables related to subject's level of training and physical performance, and, among women, with the rate of work load increment.