RPE in Lifting: The Complete Guide (with RPE Chart and RIR)

Where RPE comes from

The original RPE scale was developed by Swedish researcher Gunnar Borg in the 1960s for cardiovascular exercise and used a 6–20 scale to roughly correspond to heart rate (60–200 bpm). A simpler 1–10 (or 0–10) Borg CR-10 scale followed and is still used in cardiac rehab and aerobic training research.

The version used in strength training today is the modified RPE scale developed by Mike Tuchscherer in the late 2000s and formally studied by Michael Zourdos and colleagues in 2016. Zourdos's group validated the 1–10 scale as a reliable indicator of proximity to failure in resistance training, which is what made it usable for programming load on the fly.

The RPE/RIR chart used in resistance training

The relationship is simply RPE + RIR = 10. Memorize this and the rest of the scale follows.

Why use RPE instead of just percentages?

Traditional programs prescribe load as a percentage of your 1-rep max (e.g., "5 reps at 80 % 1RM"). The problem: your true 1RM on any given day fluctuates by 5–10 % or more depending on sleep, food, stress, and where you are in your training cycle. A fixed percentage that is correct on a fresh day is too heavy on a tired day and too light on a great day.

RPE solves this by anchoring effort to how you feel today rather than to a number you set weeks ago. The same lifter on the same lift might hit 100 kg × 5 at RPE 8 on Monday and again at RPE 9 on Friday — same load and reps, different fatigue. RPE makes that difference visible and lets you back off (or push) accordingly.

This approach is called autoregulation, and it has been the dominant programming style in modern powerlifting since roughly 2015.

How accurate is RPE, really?

A reasonable concern: it is subjective. Can you actually tell whether you had two reps left or three?

The research is encouraging but qualified:

• Helms et al. (2017, 2018) found that trained lifters estimate RIR with reasonable accuracy, particularly at loads close to failure (RPE 8–10).
• Zourdos et al. (2016) showed velocity of the bar decreases predictably as RPE increases, providing an objective anchor.
• Accuracy is worst at light loads and high RIR (an RPE of 6 or below is harder to call) and best at heavy loads near failure.
• Beginners are less accurate than intermediate and advanced lifters, but they improve with practice.

Translation: RPE is good enough for programming once you have a few months of lifting experience and have practiced the calibration. It is not a substitute for being honest with yourself.

How to use RPE in practice

As load prescription

Your program says: bench press 4 × 5 @ RPE 8.

That means: warm up, then pick a weight where the fifth rep feels like you had two reps left. If your first set is RPE 7 (three reps left), add weight on the next set. If it is RPE 9 (one rep left), the load was too heavy for the prescribed effort — drop it slightly.

As load progression

A common progression style across a four-week block on a main lift like the squat or deadlift:

• Week 1: 4 × 5 @ RPE 7
• Week 2: 4 × 5 @ RPE 8
• Week 3: 4 × 5 @ RPE 9
• Week 4: deload (4 × 5 @ RPE 6)

The load typically goes up each week even though the rep target is the same, because you are pushing closer to failure.

As autoregulation across exercises

You can also use RPE within a single session:

• Top set at RPE 9, then "back-off" sets at RPE 7 with reduced load.
• "RPE up to" prescriptions: do 3 × 8, work up to an RPE 8 set, stop when you hit it.

When NOT to use RPE

• The first few weeks of lifting. Beginners do not yet have the body awareness to gauge RIR; a simple linear progression is more effective.
• One-rep-max attempts. RPE 10 is by definition a true max, and is best measured directly.
• Speed/explosive work. Dynamic-effort training is gauged by bar speed, not by RPE.
• Conditioning and circuits. Cardiovascular RPE (Borg CR-10) is still useful here, but the resistance-training RPE-RIR mapping does not apply.

Practical tips that improve RPE accuracy

1. Calibrate with AMRAPs. Periodically do a single set "to true failure" so you remember what RPE 10 actually feels like. Most lifters underestimate how many reps they really have left.
2. Watch bar speed. Concentric speed drops sharply as RPE climbs — when the bar slows visibly, you are closer to failure than your gut suggests.
3. Log it. Write the prescribed RPE and the actual RPE side by side. Over weeks you will see your calibration error and can correct.
4. Be honest, not heroic. RPE is a measurement, not a competition. Calling everything RPE 7 when it was RPE 9 will catch up with you in a few weeks of accumulated fatigue.

RPE vs other intensity metrics

Most credible programs today use a combination — for example, percentage-based mains plus RPE-capped accessories.

How to log RPE without slowing down your workout

You only need three numbers per set: weight × reps @ RPE. For example: 100 × 5 @ 8. Anything more is overkill for most lifters.

FAQ

Bottom line

RPE is a tool for matching the day's load to the day's body. It is not magic, it is not a substitute for hard work, and it takes practice to get accurate. But once you have it, your training stops blowing up on bad days and stops leaving easy progress on good days. Log it, review it, and adjust.