Rating of perceived exertion, or RPE, is a scientifically validated way of measuring the intensity of activity based on self-reported exertion. There are two widely used scales: 6–20 and 0–10. The 6–20 scale is designed to roughly correspond with heart rate with a resting heart rate of 60BPM and a maximum heart rate of 200BPM.
Cycling Analytics supports both the 6–20 and 0–10 scales. By default, the 6–20 scale is used. The option to change this is in the profile options. It’s best to stick with one scale, but it can be changed and existing RPEs will be displayed using the new scale. How RPEs are translated between scales is shown in the tables below. A 0–100 scale is also available as an option but isn’t recommended for normal use as it’s unecessarily detailed.
For regular users, it’s best to use one scale and never change it. The rest of the details on this page don’t matter.
For coaches, RPEs are shown to your athletes according to their preference. For example, if your account is set to use the 6–20 scale but their account uses the 0–10 scale, a plan you create with an RPE of 15 will display to them as 5.5. It would probably be best if your athletes use the same scale as you. You can see which scale and change it from athlete RPE page which can be found via the “view and adjust RPE settings” button on the coaching page.
For developers, RPEs for API endpoints are specified using a 0–100 scale. This is the same as the 0–10 scale multiplied by 10. A more complicated formula is used to convert to and from the 6–20 scale as the relationship between the numbers is non-linear due to the labels used on the numbers. Internally, RPEs are handled as numbers between 0 and 100 and are displayed to the user with the closest value of their chosen scale.
What follows are tables showing how the scales convert. The tables mean, for example, that 13 (somewhat hard) is equivalent to 42 on a 0–100 scale or 4 on a 1–10 scale.
When using the 6–20 scale:
When using the 0–10 scale:
The 0–10 scale has more options than the 6–20 scale so some 0–10 values translate to the same 6–20 value. This doesn’t cause information loss if you switch scales unless you save the new value.
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