The RPE Scale (based on the research of Borg, and often called the Borg Scale) is a common method for determining exercise intensity levels based on subjective choices of descriptions of the exercise intensity. There are several versions of the scale available, the RPE 1-10, RPE 1-20 and this more finely-graded CR-Scale that goes up to 100.
The CR100 (centiMax) scale varies from 0 to 100 with the verbal descriptors placed where they belong on a ratio scale. The 0 level on the scale is described as “nothing at all”, and 100 is described as maximum. In between these points the descriptors minimal, extremely weak, very weak, weak, moderate, somewhat strong, strong, very strong, and extremely strong are interspersed.
The level rated as maximum is based on the previous experience of a maximal perceived exertion, therefore the scale also allows for absolute maximum, a value above 100 which can be given by the subject if they produce or perceive an intensity never needed or experienced before.
It is important to have a standard introduction and explanation of the instructions. Here is an example of the instructions used by Molander et al. (2013).
“Use this rating scale to tell how strong your experience is. Your experience can be about effort, pain, or something else. One hundred (“Maximum”) is a very important level of intensity. This level is to be considered as a referential point on the scale. It is the strongest experience or feeling (for example, from effort) you ever had. Still, it is possible to experience or imagine something even stronger. For that reason there is on the scale “Absolute maximum” at the top of the scale, marked with a “•”. If your experience or feeling is stronger than 100, you can use a higher number. Usually the intensity in our experiences is not as strong as 100, and often numbers below 2–3 are not needed either. The scale works as a percentage scale, and there is very good agreement between what the verbal expressions means and what the numbers stand for”
- Borg GAV. Borg’s Rating of Perceived Exertion and Pain Scales. Champaign, IL: Human Kinetics, 1998.
- Borg G., Borg E. (2001). A new generation of scaling methods: level-anchored ratio scaling. Psychologica 28, 15–45
- Borg E., Kaijser L. (2006). A comparison between three rating scales for perceived exertion and two different work tests. Scand. J. Med. Sci. Sports 16, 57–69
- Molander, B., Olsson, C.-J., Stenling, A., & Borg, E. (2013). Regulating Force in Putting by Using the Borg CR100 scale®. Frontiers in Psychology, 4, 82. http://doi.org/10.3389/fpsyg.2013.00082
- See more about using the RPE scales, including another very similar RPE scale, with the ratings between 6-20.
- See also the variation of this 10 point scale using hand signals, and Rob's 5-Point Rate of Perceived Exertion Scale
- PA-R, a scale for rating physical activity.
- Rating-of-fatigue (ROF) — a scale to rate how fatigued someone is feeling.
- Reps in Reserve (RIR) — how many more strength lifts can you do?
- Other athlete questionnaires
- About the Likert Scale