Wheelchair users' perceived exertion during typical mobility activities

Study design: Each participant performed a series of wheelchair exercises equivalent in intensity to minimal functional speed (1 m s −1 ), functional walking speed (1.3 m s −1 ), a relatively challenging speed (1.6 m s −1 ) and a self-selected speed. Each participant also completed a graded exercise test (GXT) to volitional exhaustion (VO 2peak ). Objectives: The purpose of this study was (1) to assess the physical capacity of wheelchair users as they undertake typical mobility activities and (2) to investigate how closely the components of a differentiated model of perceived exertion mirror wheelchair users' own perception of exertion. Methods: Eleven (eight males and three females) spinal cord-injured or congenitally impaired wheelchair-dependent participants volunteered for the study. Differentiated ratings of perceived exertion (RPE _arm and RPE _respiration ) and oxygen uptake (VO 2 ) and heart rate were recorded during each exercise. Results: The mean comfortable speed at which the participants propelled their own wheelchairs on the wheelchair ergometer was 1.1±0.2 m s −1 . Speeds of 1 m s −1 and 1.3 m s −1 are typical of everyday functional propulsion. The corresponding RPE_ respiration and RPE_ arm ranged from 7 to 13 on the Borg scale; the %VO 2peak measured in these trials ranged from 37 to 80% VO 2peak. For propulsion intensities used in the present study—low, moderate, high and graded exercise intensity—no difference could be observed between RPE _respiration and RPE _arm . There were no significant differences between RPE _arm and RPE _respiration at the termination of the GXT. Conclusion: The current study showed potential for the use of RPE to assess and monitor daily wheelchair propulsion intensity in individuals with paraplegia.