Embracing the Wild: The Power of RPE in Ultra Running

By Libbi | The Running Nomads

Rate of Perceived Exertion, or RPE, is a subjective scale used to assess an individual’s perception of their own effort during physical activity. RPE is an effective metric for ultra runners to use to determine the desired intensity of their runs, rather than better-known metrics such as minute mile/kilometre pace or heart rate zones.

This is because it allows athletes to gauge how hard they feel they are working, whilst taking into account physiological and psychological factors that contribute to their exertion levels such as, environmental conditions like terrain, elevation and temperature changes, muscle fatigue, mental state and overall wellbeing. 

What is RPE?

The RPE (CR10) scale was created by Dr. Gunnar Borg, a Swedish psychologist, in the 1960s¹. It ranges from 1 to 10 – 1, corresponding to barely any exertion or walking pace, up to 10, being maximal output intensity, like an all-out sprint that can only be maintained for a very short time.

RPE is rooted in the idea that an individual’s perception of effort is closely tied to physiological responses such as heart rate, oxygen consumption and lactate production. If you feel like you’re pushing yourself during a session, it’s likely your heart rate will be elevated.