The reliability of oxygen consumption (VO2), heart rate (HR), and rating of perceived exertion (RPE) at three different workloads was examined during an arm cranking exercise task. Nine persons with multiple sclerosis (MS) and confined to a wheelchair each performed two sessions of discontinuous, submaximal aerobic test on an arm ergometer. Comparisons of the test scores and generalizability theory were used to analyze the data. Both HR and VO2 were found to be reliable measures under the conditions used in this study. RPE at the same workloads was found to be rather unreliable. Overall, the use of RPE as an indicator of exercise intensity instead of HR appears to be unjustified by the results of this study. Therefore, practitioners who want a quick and efficient method of measuring exercise intensity should use HR instead of RPE for persons with multiple sclerosis.
L.J. Holland is with the Rick Hansen Centre, Univ. of Alberta, and M. Bouffard is with the Dept. of Physical Education and Sports Studies, Univ. of Alberta, Edmonton, Alberta, T6G 2H9. D. Wagner is with the Dept. of Physical Education, Univ. of Calgary, Calgary, Alberta, T2N 1N4.