In sports and particularly exercise testing, the rating of perceived exertion (RPE), as measured by the Borg rating of perceived exertion scale (RPE scale), is a frequently used quantitative measure of perceived exertion during physical activity. In medicine this is used to document the patient's exertion during a test, and sports coaches use the scale to assess the intensity of training and competition. The original scale introduced by Gunnar Borg rated exertion on a scale of 6-20. Borg then constructed a category (C) ratio (R) scale, the Borg CR10 Scale. This is especially used in clinical diagnosis of breathlessness and dyspnea, chest pain, angina and musculo-skeletal pain. The CR-10 scale is best suited when there is an overriding sensation arising either from a specific area of the body, for example, muscle pain, ache or fatigue in the quadriceps or from pulmonary responses.
The Borg scale can be compared to other linear scales such as the Likert scale or a visual analogue scale. The sensitivity and reproducibility of the results are broadly very similar, although the Borg may outperform the Likert scale in some cases.
The Borg RPE scale is a numerical scale that ranges from 6 to 20, where 6 means "no exertion at all" and 20 means "maximal exertion." When a measurement is taken, a number is chosen from the following scale by an individual that best describes their level of exertion during physical activity.
A component that appears to integrate many variables during whole-body exercise is the rating of perceived exertion (RPE) . ...
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Aside from accounting for the reduced performance of mentally fatigued participants, this model rationalizes the reduced RPE and hence improved cycling time trial performance of athletes using a glucose mouthwash (Chambers et al., 2009) and the greater power output during a RPE matched cycling time trial following amphetamine ingestion