RPE
RPE, or rating of perceived exertion, is a subjective 1–10 score for how hard a set was; in strength training a 10 means no repetitions left in reserve and an 8 means about two were.
A log that records only weight and reps loses the most important part of a set: how close to the limit it was. Three sets of eight at 60 kg can be comfortable or brutal, and next week's decision depends on which it was.
The scale in practice
10 means you could not have done another repetition. 9 means one more was there. 8 means two. 7 means three. Below 7 the set is usually too easy to drive much adaptation, though there are good reasons to train there during technique work or a deload.
Why it is more useful than it sounds
Strength varies day to day by more than most people expect — sleep, stress, food, time of day. A fixed percentage of your one-rep max is heavy on a bad day and light on a good one. Rating the set instead lets the load follow your actual capacity while the intent stays constant.
Its weakness
Beginners rate poorly, almost always underestimating how many repetitions they had left. It takes a few months of occasionally taking a set to genuine failure before the scale calibrates. Until then, record it anyway: the number becomes useful precisely by being recorded and corrected.
Sources
- 1.Physical Activity Guidelines for Americans — US Department of Health and Human Services
- 2.Evidence-based recommendations for natural bodybuilding contest preparation — Journal of the International Society of Sports Nutrition
Related reading
- What to record in a training log, and what to skip
Four fields carry nearly all the information. A field-by-field account of what earns its place, what does not, and why the effort field matters most.
- RPE and RIR: how to rate a set you just did
Two scales for the same thing, why the number belongs in your log, and how to calibrate a rating that most beginners get wrong by three repetitions.
- How to log your workouts in under a minute
A training log answers one question next week: did I do more than last time? What to record, what to skip, and how to read progress out of it.
- Training volume or intensity: what to track
Volume drives growth, intensity drives strength, and both are measured badly by tonnage. What each term means and which number belongs in your log.