Complete Guide to RPE and RIR: Master Intensity to Maximize Your Gains

It’s happened to you for sure: you go to the gym, follow your routine to the letter, but some days the weight feels like a feather and other days it feels like gravity has decided to pick on you. If you always train with the same weight “because that’s what the paper says,” you’re leaving results on the table. This is where RPE and RIR come in — the ultimate tools to stop guessing and start training for real.

In this article, we’ll break down what these scales are, why they’re superior to simply “training to failure,” and how you can implement them today so every set counts.

What Are RPE and RIR?

To progress, it’s not enough to move weight; you need to control the stimulus. If you train too light, you don’t grow. If you always train at the limit, you burn out.

RIR (Reps in Reserve)

RIR, or Reps in Reserve, is a scale that measures how many more reps you could have done before your technique broke down or you simply couldn’t complete another rep.

• RIR 0: You reached technical muscular failure. You couldn’t do one more.
• RIR 2: You did your set, but felt you could have completed two additional reps with good form.

RPE (Rate of Perceived Exertion)

RPE is the Rate of Perceived Exertion. Originally created by Gunnar Borg for cardio, it was adapted to strength training by Mike Tuchscherer. It’s scored from 1 to 10.

• RPE 10: Maximum effort. Zero reps possible (Equivalent to RIR 0).
• RPE 9: You could have done one more (RIR 1).
• RPE 8: You could have done two more (RIR 2).

The Relationship Between Them

Basically, they’re two sides of the same coin. While RIR focuses on what you have “left in the tank,” RPE focuses on “how hard it felt.” In the modern gym, we typically use the RPE scale based on reps in reserve because it’s the most precise for weightlifting.

RPE	RIR	Effort Description
10	0	Maximum effort. Couldn’t do more reps or lift more weight.
9.5	-	Couldn’t do more reps, but maybe a bit more weight.
9	1	Could have done one more rep.
8.5	-	Could have done one more safely, maybe two.
8	2	Could have done two more reps.
7	3	Could have done three more reps.
5-6	4-6	Moderate effort. Weight moves fast.

Why Should You Use Self-Regulation?

The problem with rigid routines (e.g., “Do 4x10 with 80kg”) is that they don’t account for your daily context. Work stress, hours of sleep, what you ate three hours ago, or even your mood all affect your absolute strength that day.

1. Fatigue Management

If you slept only 4 hours and a weight that’s normally RPE 8 feels like RPE 10, forcing the programmed routine will only accumulate unnecessary fatigue or, worse, lead to injury. RPE lets you adjust the load to maintain the right stimulus without destroying your central nervous system.

2. Stimulus Specificity

For hypertrophy, the science is clear: sets should be close to failure (RIR 1-3). Using RPE ensures that regardless of circumstances, you’re in the “gain zone.” In Gymary, you can log these values each session to visualize if your perceived effort decreases over time with the same weight — a key indicator you’ve gotten stronger.

3. Avoid Plateaus

Training to failure (RPE 10) every session is a recipe for long-term disaster. By using RIR, you can program weeks at RIR 3, progress to RIR 1, then deload. This periodization is what builds elite physiques.

How to Implement RPE in Your Training

I won’t lie: learning to measure your effort is a skill. At first, most beginners err on the conservative side (they think they’re at RPE 9 when they’re actually at RPE 6).

The Learning Process

1. Record yourself: Sometimes what feels like a super slow rep (RPE 9) looks smooth on video. If bar speed doesn’t drop drastically, you probably had more in the tank than you thought.
2. Test failure occasionally: Once a month, on a safe exercise (like a leg extension machine or leg press), go all out. See how many reps you can do when you think you can’t do any more. That’ll give you a real reference for what RIR 0 actually is.
3. Be honest: Don’t inflate your numbers. If you logged RPE 8 but deep down know you could have done 5 more, correct it.

Practical Example of a Self-Regulated Routine

Imagine you have programmed squats: 3 sets of 6 reps at RPE 8.

• Set 1: You load 100kg. You do the 6 reps and feel you could have done 4 more (RPE 6). Verdict: Too light.
• Set 2: You go up to 110kg. You do the 6 reps and feel you could have done 2 more. Verdict: Bingo! RPE 8.
• Set 3: You keep 110kg. Due to accumulated fatigue, the last reps are harder. You finish the 6 reps and feel you could only have done one more (RPE 9).

When you’re done, log this data in your training log. Using an app like Gymary makes your life easier here, as it lets you see the effort history from previous weeks and decide whether today is the day to increase the weight or if you should maintain it to solidify technique.

Common Mistakes When Using RPE and RIR

Even intermediate athletes make mistakes using these scales. Avoid these three typical pitfalls:

1. “Ego-RPE”

It’s the opposite of being conservative. It’s when someone logs RPE 8 but the last rep took 4 seconds to go up, their face turned beet red, and technique completely broke down. That’s an RPE 10 or even a technical failure. Be objective.

2. Using It on Inappropriate Exercises

It doesn’t make much sense to measure RPE on very light isolation exercises or extreme stability work. RPE shines on compound exercises (squats, presses, rows, deadlifts). On a bicep curl, it’s better to focus on mind-muscle connection and getting close to failure.

3. Forgetting Progressive Overload

RPE is a tool to measure intensity, not an excuse not to push yourself. If all your sessions are RPE 7 and you never try to increase weight or reps, you’ll plateau. The goal of RPE is to help you push intelligently, not to give you permission to train at half throttle.

Suggested Strategy for Your Next Mesocycle

If you want to try this system, here’s a suggested intensity progression for a 4-week block:

• Week 1 (Introduction): Work at RPE 7 (RIR 3) on all your main exercises. Leave room to get used to the volume.
• Week 2 (Consolidation): Increase intensity to RPE 8 (RIR 2). Start feeling the weight for real.
• Week 3 (Overreach): Push up to RPE 9 (RIR 1). This is where the growth magic happens.
• Week 4 (Deload): Drop to RPE 5-6. Reduce weight and sets by half. Allow your body to recover so you can start the next block stronger.

Conclusion

RPE and RIR aren’t just numbers; they’re the key to understanding your body. They take away the anxiety of having to hit an arbitrary number when you’re not feeling great and give you the “green light” to crush your personal records when you’re feeling like a beast.

Remember that consistency is king, but consistency with appropriate intensity is what separates an average lifter from an advanced one. Start logging your RPE today, analyze your data, and let self-regulation take you to the next level. Go hard!