Rate of Perceived Exertion or the Borg Rating of Perceived Exertion (RPE) is a way of measuring physical activity intensity level. 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 RPE scale – A.K.A. Borg scale (6-20)
The original scale introduced by the Swedish psychologist Dr. Gunnar Borg, rated exertion on a scale of 6-20; as a simple way to estimate heart rate—multiplying the Borg score by 10 gives an approximate heart rate for a particular level of activity. It is based on the physical sensations a person experiences during physical activity, including increased heart rate, increased respiration or breathing rate, increased sweating, and muscle fatigue.
The seemingly odd range of 6-20 is to follow the general heart rate of a healthy adult by multiplying by 10. For instance, a perceived exertion of 12 would be expected to coincide with a heart rate of roughly 120 beats per minute.
| How you might describe your exertion | Borg rating | Examples (for most adults under 65 y.o.) |
|---|---|---|
| None | 6 | Reading a book, watching television. |
| Extremely light | 7 to 8 | Tying shoes. |
| Very light | 9 to 10 | Chores like folding clothes that seem to take little effort. |
| Fairly light | 11 to 12 | Walking through the grocery store or other activities that require some effort but not enough to speed up your breathing |
| Somewhat hard | 13 to 14 | Brisk walking or other activities (like riding a bike at an easy pace) that require moderate effort and speed your heart rate and breathing but don’t make you out of breath. |
| Hard | 15 to 16 | Activities that take vigorous effort and get the heart pounding and make breathing very fast. Like climbing with a bike at a moderate pace. |
| Very hard | 17 to 18 | The highest level of activity you can sustain: like time-trialing or climbing with a bike at your highest sustainable pace. |
| Extremely hard (Maximum exertion) | 19 to 20 | A finishing kick in a race or other burst of activity that you can’t maintain for long. |
The simplified RPE scale (0-10)
The Borg scale is good to follow but it’s a little clumsy using the numbers 6 through 20. There are other RPE scales based on the Borg scale, one common version uses a simplified scale of 0 to 10:
| How you might describe your exertion | rating | Examples (for most adults under 65 y.o.) | HR%[1] |
|---|---|---|---|
| None | 0 | Reading a book, watching television. | 0 |
| Extremely light | 1 | Tying shoes | 20-30 |
| Very light | 2 | Chores like folding clothes that seem to take little effort | 30-40 |
| Moderate | 3 | Walking through the grocery store or other activities that require some effort but not enough to speed up your breathing | 40-50 |
| Somewhat hard | 4-6 | Brisk walking or other activities (like riding a bike at an easy pace) that require moderate effort and speed your heart rate and breathing but don’t make you out of breath. | 50-70 |
| Hard | 7-8 | Activities that take vigorous effort and get the heart pounding and make breathing very fast. Like climbing with a bike at a moderate pace. | 70-80 |
| Very hard | 9 | The highest level of activity you can sustain: like time-trialing or climbing with a bike at your highest sustainable pace. | 80-90 |
| Extremely hard (Maximum exertion) | 10 | A finishing kick in a race or other burst of activity that you can’t maintain for long. | 90-100 |
Notes
[1] How to calculate your heart rate percentage? First you have to learn your resting and maximum heart rates. Then we can calculate P% of heart rate as below:
HR = min. heart rate + ((Max. heart rate – min. heart rate) x P / 100)
Let’s assume that your max. heart rate is 180 and resting heart rate is 60. We can calculate 80% heart rate as:
HR = 60 + ((180 – 60) x 80 / 100) = 156
Your heart rate at 80% should be 156. The formula gives your min. heart rate at 0%, and your max. heart rate at 100%.
Sources
- Borg Scale on Wikipedia
- Centers for Disease Control and Prevention
- intervalsforcardio.com
- Harvard School of Public Health – The Borg Scale of Perceived Exertion