RPE explained: training by effort, not just numbers

RPE stands for Rate of Perceived Exertion. In strength training it answers one question: how many more reps could you have done?

The scale

An RPE 10 set means you could not have done another rep. RPE 9 means one rep left in the tank, RPE 8 means two, and so on. Most productive training happens between RPE 6 and 9.

Why use it

Your strength changes day to day with sleep, stress and food. A fixed weight can be too easy on a good day and too heavy on a bad one. Rating effort lets the load follow how you actually are.

How we use it in the SLF app

Every set in your program has a target RPE. When you log the weight, reps and RPE you actually hit, the app estimates your 1RM from it, and I use those trends to set next week's loads.