Research

Adherence

Intra-set Rating of Perceived Exertion (RPE) and Repetitions in Reserve (RIR) predictions are significantly more accurate when made closer to muscular failure (9 RPE) compared to earlier in the set (6 RPE) during squat, bench press, and deadlift exercises.

When using RPE or Reps in Reserve (RIR) to guide your training, do not rely on your feeling at the beginning of the set. Your ability to accurately predict how many reps you have left is significantly worse when you are far from failure (e.g., 6 RPE). To use RPE effectively, make your assessment when you are close to failure (e.g., 9 RPE), as this is when your perception of effort aligns best with actual performance.

ModerateSupportsMEDIUM confidence
These results suggest that intra-set RPE ratings are more accurate closer to failure on all three exercises
Nicholas M. Sautter et al. · Medicine & Science in Sports & Exercise · 2019

Why this rating

Small sample size (n=10), short-term acute study, counterbalanced order but limited generalizability to untrained populations.

Source

Proximity To Failure And Repetitions Per Set Effect Rpe Accuracy In The Squat, Bench Press, And Deadlift

Nicholas M. Sautter et al. · Medicine & Science in Sports & Exercise · 2019

DOI 10.1249/01.mss.0000563313.87191.c2

crossover · n=10
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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