The rate of perceived exertion scale is a way of measuring your exercise intensity. A zero RPE means you’re using the same effort you would to sit; a 5 represents a moderate level of intensity ...

The RPE scale has been widely researched and has become the standard for measuring perceived exercise exertion. The RPE scale ranges from one to 10 (whereas the BORG scale ranges from 6-20).

Amongst HRV, HIIT and VO2 max, you might have encountered RPE or, to give it its full title, rate of perceived exertion ... he prefers RPE as a measure of intensity, too.

Evidence shows that the ANS and rating of perceived exertion (RPE) regulate exercise performance ... RPE, heart rate (HR) and R–R intervals (as a measure of ANS function) were recorded continuously ...