Question 1

What is RPE (Rating of Perceived Exertion)?

Accepted Answer

RPE is a subjective scale (usually 1-10) for strength intensity. In lifting, RPE 10 represents absolute failure; you couldn't do another rep or add any weight. RPE 9 means it was hard, but if pushed to the limit, you could have done 1 more.

Question 2

What is the relationship between RPE and RIR (Reps in Reserve)?

Accepted Answer

They are two sides of the same coin. RIR is 'Reps in Reserve', meaning how many more you could do. The formula is:

RIR = 10 - RPE

For example, an RPE 8 target means you choose a weight where you feel you have 2 reps left in the tank.

Question 3

Why use RPE instead of fixed percentages (e.g. 80% 1RM)?

Accepted Answer

A 1RM test shows your best performance on one specific day. Your daily strength can fluctuate by 5-10% due to sleep, stress, or nutrition. RPE allows you to 'train with the energy you have today', preventing injury and ensuring optimal progress. This is the gold standard for advanced lifters.

Question 4

How do I use the 'Weight Target Matrix'?

Accepted Answer

If you lift 100kg for 5 reps at RPE 8, input it to find your e1RM. If your plan then calls for '5 reps @ RPE 9', simply check the matrix intersection of the '5 Reps' row and '@9' column to know exactly what weight to load next—no mental math required!

RPE / RIR Calculator

Calculation Base

Training Data

Scientific Guide (FAQ)