# How to judge reps in reserve: a practical method for rating sets honestly Updated: 2026-08-23 Published: 2026-08-23 Canonical page: https://methodapp.net/how-to-judge-reps-in-reserve Homepage: https://methodapp.net/ RIR is a judgement, and judgements can be trained. This guide gives a calibration routine, the bar-speed and effort cues that matter, the common ways ratings drift, and what Method does with the value so you know why it is worth getting right. > **In short.** Judge reps in reserve by comparing the last rep you did to what your last possible rep feels like. Calibrate that memory on purpose, by occasionally taking a safe movement to failure, then rate working sets against it. Use bar speed on the concentric as the main cue and expect accuracy to be good at 0 to 2 RIR and rough above 4. Log a whole or half number, be consistent rather than optimistic, and treat a failed rep as zero. Method uses the value you log for estimated 1RM, records, and suggested loads, so consistency pays. ## Why the estimate matters Reps in reserve turn a set into a comparable number. Method folds the RIR you log into the estimated 1RM, compares that estimate across sessions for records, and uses your last set's RIR to suggest the next load. If your ratings wander, those numbers wander with them. None of that needs you to be perfectly right. It needs you to be consistently you. ## A calibration routine 1. **Pick a safe, stable movement.** A machine press, a dumbbell row, a leg press. Something you can take to failure without a spotter and without technique collapsing. 2. **Take one set to true failure** at a weight you would normally rate around 2 RIR. Count the reps. Notice how reps 1 to n−3 felt, how n−2 and n−1 felt, and what the final, failed rep felt like. 3. **Write it down.** "I rated this as 2 RIR and got 3 more" is the whole point. Do this once every few weeks per movement pattern, not every session. 4. **Rate working sets against that memory.** When you stop a set, ask "how many more like that last one could I have done with the same form." Answer in whole or half reps. The evidence says this is the normal pattern. In 25 trained men squatting to failure at 70 percent of 1RM, the error in predicted reps in reserve was about 2 reps when they called 1 RIR, about 3.7 reps at 3 RIR, and about 5 reps at 5 RIR, and more total reps in the set made predictions worse [1]. In 81 adults across a wide range of experience, error was about one rep when 0 to 5 reps remained and more than two when 7 to 10 remained, and experience did not change accuracy [2]. A meta-analysis of 12 studies found an average underprediction of about one rep, with accuracy slightly better closer to failure and in sets of 12 reps or fewer [3]. The fix is exposure, not trying harder. ## Cues that predict failure **Bar speed on the concentric.** The most reliable cue for barbell and machine work. Average bar velocity and RIR-based RPE were strongly and inversely related in the squat in both experienced and novice lifters [4]. A clear slow-down relative to the first rep usually means two to three reps left; a grind with a sticking point usually means one or none. **Form drift.** Elbows flaring, hips rising early, the bar path bending forward. Form changes are a sign of proximity to failure; a set you stop because form is going is often at 1 to 2 RIR. **Rep-to-rep change.** If the last rep felt like the one before it, you likely had more than two left. If it felt clearly different, you were close. **Breathing and urge to stop.** Useful but personal. Some people want to stop at 4 RIR; some do not notice until 1. Calibration tells you which you are. ## Where ratings go wrong - **Rating by plan instead of by set.** The prescription says 2 RIR, so the set gets logged as 2 RIR. Rate what happened. - **Rating by fatigue instead of reps.** Feeling tired after a set is not the same as being out of reps. The question is how many more reps of that quality you could have done. - **Changing the standard across sessions.** A hard day rated generously and an easy day rated harshly produce noise. Keep the standard even and let the weight tell the story. - **Ignoring half values.** "Maybe one, maybe two" is 1.5. Method accepts half values, and the suggested-load calculation uses them. ## What Method does with the number - **Estimated 1RM** uses reps plus reps in reserve as effective reps. Logging 5 reps at 2 RIR is read as a set of 7 to failure. - **Records** compare estimated 1RM, so an overrated RIR can create a false record and an underrated one can hide a real one. - **Suggested loads** read the RIR on your last eligible set and the RIR target on the next set. If you rate sets consistently, the suggestion is consistent. - **Display scale** is your choice. Log in RIR or RPE; Method stores one value and shows either. See [RIR vs RPE](/rir-vs-rpe). ## When not to bother Warm-ups do not need a rating. Technique work at light loads does not need one. Very high rep sets, above 12 to 15, are hard to rate; both the squat study and the meta-analysis found accuracy falls as the total reps in a set rise [1][3], and the estimate formula is rough there anyway, so a coarse number is fine. Save the precision for the working sets that drive the numbers. ## Common questions ### How do I know how many reps I had left? Compare the last rep to how you move near failure. A clear slow-down on the concentric, a change in bar path, and the urge to stop all arrive in the last two or three reps. Occasionally take a set to failure on a safe movement to anchor what zero feels like, then rate working sets against that memory. ### Is it better to overestimate or underestimate RIR? Neither. Consistency matters more than direction, because your estimated 1RM, records, and suggested loads all read the number you log. A steady bias is harmless; a bias that changes week to week makes the numbers noisy. ### Should beginners use RIR? Yes, with a wide margin and low stakes. Rate sets, expect to be wrong, and check against occasional sets to failure on machines or dumbbells. Accuracy improves with exposure. Method accepts whole and half values so you can rate coarsely at first. ### What RIR should I log for a set I did not finish? Zero, and the reps you actually completed. A set that ended on a failed rep is at failure by definition. ## References 1. Zourdos MC, Goldsmith JA, Helms ER, Trepeck C, Halle JL, Mendez KM, Cooke DM, Haischer MH, Sousa CA, Klemp A, Byrnes RK. Proximity to Failure and Total Repetitions Performed in a Set Influences Accuracy of Intraset Repetitions in Reserve-Based Rating of Perceived Exertion. Journal of Strength and Conditioning Research, 2021. https://pubmed.ncbi.nlm.nih.gov/30747900/ 2. Hackett DA, Cobley SP, Davies TB, Michael SW, Halaki M. Accuracy in Estimating Repetitions to Failure During Resistance Exercise. Journal of Strength and Conditioning Research, 2017. https://pubmed.ncbi.nlm.nih.gov/27787474/ 3. Halperin I, Malleron T, Har-Nir I, Androulakis-Korakakis P, Wolf M, Fisher J, Steele J. Accuracy in Predicting Repetitions to Task Failure in Resistance Exercise: A Scoping Review and Exploratory Meta-analysis. Sports Medicine, 2022. https://pubmed.ncbi.nlm.nih.gov/34542869/ 4. Zourdos MC, Klemp A, Dolan C, Quiles JM, Schau KA, Jo E, Helms E, Esgro B, Duncan S, Garcia Merino S, Blanco R. Novel Resistance Training-Specific Rating of Perceived Exertion Scale Measuring Repetitions in Reserve. Journal of Strength and Conditioning Research, 2016. https://pubmed.ncbi.nlm.nih.gov/26049792/ ## About this page Method writes and maintains this page. Every statement about Method is checked against the shipped product. For general references, link to https://methodapp.net/.