In sports and in particular stress tests, the perceived effort assessment (EPR), measured by the Borg scale of the perceived effort scale (EPR scale), is a frequently used quantitative measure of perceived exertion during physical activity. In medicine, this serves to document the patient’s effort during a test, and athletic trainers use the scale to assess the intensity of training and competition. The original scale introduced by Gunnar Borg evaluated the effort on a scale of 6-20. Borg then built a category scale (C) (R), the Borg CR10 scale. This is particularly used in the clinical diagnosis of shortness of breath and dyspnea, chest pain, angina and musculoskeletal pain. The CR-10 is best when there is a dominant sensation from either a specific area of the body, such as muscle pain, quadriceps pain or fatigue, or lung 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 overall very similar, although the Borg can surpass the Likert scale in some cases.
The Borg EPR scale is a numerical scale from 6 to 20, where 6 means “no effort at all” and 20 means “maximum effort”. When a measurement is taken, a number is chosen from the following scale by an individual who best describes his level of effort during physical activity.