Differentiated ratings of perceived exertion during physical exercise.

The typical overall (undifferentiated) rating of perceived exertion (RPE) appears to represent an individual's integration of various physiological sensations that have different subjective weightings. Two categories of physiological factors have been suggested as major determinants of RPE during physical exercise. These two factors are a local factor that relates to sensations or feelings of strain from the exercising muscles and/or joints and a central factor relating primarily to cardiopulmonary sensations. This paper attempts to characterize the relative importance of the various physiological cues in the exertional rating pertinent to these local and central factors. The majority of the related literature suggests that local factors are usually perceived as dominant; however, recent findings that evaluate differentiated RPE during exercise at high altitude imply a greater importance for central factors. When a particular physiological cue is markedly altered over others during exercise, it appears that the resultant sensation can easily dominate the overall RPE. In contrast, when this particular cue is not changed during exercise, as the result of some experimental manipulation or intervention, then another cue can become pronounced. Finally, an experimental model for evaluating differentiated RPE that allows comparisons between local and central exertion and further comparison to the general or overall exertion is discussed.