Evolution of perceived exertion concepts and mechanisms: a literature review

Abstract

The mechanisms and concepts of perceived exertion have changed over the years. Thus, the objectives of the present literature review were i) to investigate the literature reviews that have been published since 1982 and to describe the proposed causal mechanisms of perceived exertion, and ii) to determine whether the concepts of perceived exertion have accompanied the changes of its proposed mechanisms. Searches were performed in PubMed, Science Direct and Scielo using the terms 'rating of perceived exertion and review' and 'perceived exertion and review'. Eighteen papers whose main objective was to determine the overall perceived exertion during physical exercise were included in the present study. It was observed that, despite the existence of the early corollary discharge theory, after Borg's propositions most of the literature has explained perceived exertion using the afferent feedback theory based on correlational studies. It was only in 2009 that there was a resurgence of the original corollary discharge theory in perceived exertion papers. Most of the perceived exertion concepts are related to the afferent feedback mechanism, using constructs such as physiological responses, stress, discomfort and pain. However, these constructs are incongruent with the corollary discharge theory, presenting physiological mechanisms that differ from those of perceived exertion. Therefore, Borg's studies have influenced contemporary views of the mechanisms and concepts of perceived exertion. Over the years, additional constructs have been incorporated into the original Borg's concept, although always on the basis of the afferent feedback theory.

Os mecanismos e conceitos da percepção de esforço têm mudado ao longo do tempo. Assim, este artigo de revisão de literatura tem por objetivos: i) investigar as revisões de literatura publicadas a partir de 1982, descrevendo os mecanismos causais de geração da percepção de esforço relatados e; ii) verificar se os conceitos da percepção de esforço acompanharam as mudanças que ocorreram acerca dos seus mecanismos causais. Foram realizadas buscas nas bases de dados PubMed, Science Direct e Scielo com os termos “rate perceivedexertionandreview” e “perceivedexertionandreview”. No total, foram incluídos 18 artigos, que tiveram como objetivo principal a percepção geral de esforço em exercício físico. Apesar da antiga existência da teoria do Disparo corolário para explicar os mecanismos causais da percepção de esforço, verifica-se que, após as proposições de Borg, a maior parte da literatura descreve a percepção de esforço através do mecanismo de Feedback aferente, baseada em estudos correlacionais. Apenas em 2009, a teoria original do Disparo corolário reaparece. Quanto aos conceitos, a maioria deles remete ao mecanismo de feedback aferente, utilizando-se de constructos como respostas fisiológicas, estresse, desconforto e dor, que são incongruentes com a teoria do Disparo corolário e apresentam mecanismos distintos aos da percepção de esforço. Portanto, verificou-se que os estudos de Borg influenciaram nos mecanismos e conceitos contemporâneos da percepção de esforço. Com o passar do tempo, houve incorporação de constructos no conceito original de Borg, porém, sempre embasado na teoria do Feedback aferente.