Influence of local and central factors in dominating rated perceived exertion during physical work.

The literature suggests two major factors determine rated perceived exertion during physical work. These two factors are a local factor, i.e., sensations or feelings of strain in the working muscles and/or joints; and a central factor, i.e., sensations or feelings primarily associated with the cardiorespiratory systems. In some experiments heart rate and minute ventilation (central vactors) appear to be the dominant cues for rated perceived exertion, while in others, local factors such as blood lactate concentration and muscular discomfort seem to be the prominent cues. However, it appears that when a particular cue is accentuated by either elevated rate, concentration or value over others it can dominate the over-all rating of perceived exertion. After evaluating the existing literature, a model has been introduced to evaluate differentiated ratings of perceived exertion (local and central) in comparison to the over-all measure. This model may help aid in a better understanding of the mechanisms by which the subjective perception of exertion is determined during different types of physical work.