The effectiveness of a program depends on choosing the right level of effort. Work, sleep, stress, focus, type of equipment, familiarity with it, and of course fatigue all play a role. Depending on the source, programs typically provide a broad prescription like “3×10” with little indication of the expected intensity, or rely on more advanced methods such as %1RM, based on pre-calculated loads and usually suited for experienced athletes.
The in-between we use at Desk Athletics, which allows you to train with structure and autonomy, lies in understanding two simple concepts: Repetitions in Reserve (RIR) and Rate of Perceived Exertion (RPE).
Fixed weights and percentages don’t always work
Percentage-based systems and fixed loads can be effective in controlled environments. They assume stable conditions, frequent testing, and a good understanding of strength levels. For most people, especially recreational athletes, that’s not the case.
Day-to-day performance fluctuates: energy, recovery, and external stressors change how a given weight feels. A load that was appropriate last week might feel too easy or too demanding today. Without a way to adjust, training becomes inconsistent. Some sessions miss the intended stimulus, others push too far.
Adjusting the effort
Instead of trying to match a number, you can match the intended level of effort. This approach allows training to adapt to the day while keeping the overall structure intact. Sessions remain productive without relying on exact loads. RIR and RPE are practical tools to make that adjustment.
What is RIR (Repetitions in Reserve)
RIR refers to how many repetitions you could still perform at the end of a set while maintaining proper form.
It provides a simple way to quantify effort without needing to know exact weights or percentages.
- RIR 4 → several reps left, light effort
- RIR 3 → moderate effort
- RIR 2 → solid working set
- RIR 1 → hard, close to limit
- RIR 0 → no reps left, maximal effort
Instead of aiming for a specific load, you adjust the weight or difficulty until the set matches the target. It makes it easy to work with resistance bands (you step further away or closer to the support, shorten the band, etc.), or to play around with tempo or alternate forms of bodyweight exercises.
What is RPE, and how it relates to RIR
RPE (Rate of Perceived Exertion) describes how hard an effort feels on a scale from 1 to 10. It is especially useful when monitoring the intensity of a full session, or of any work that isn’t repetition-based (like a plank or a running session, for example).
❗It is not a linear scale. It applies across different types of training, not just strength work.
- RPE 3 → moderate
- RPE 5–6 → somewhat difficult
- RPE 7 → hard
- RPE 8 → very hard
- RPE 9 → near maximal
- RPE 10 → maximal
For strength training, RPE and RIR align closely:
- RPE 7 ≈ RIR 3
- RPE 8 ≈ RIR 2
- RPE 9 ≈ RIR 1
- RPE 10 = RIR 0
RIR is often easier to apply to repetitions-based work.
RPE becomes more useful for timed efforts, conditioning, or isometric holds.
Why this approach works
Adjusting effort rather than fixing loads makes training more adaptable.
- It accounts for daily fluctuations in energy and recovery
- It removes the need for frequent testing
- It allows consistent training even with variable schedules
- It improves awareness of effort over time
The objective is not to hit a number, but to reach the intended training stimulus.
How to use RIR/RPE in practice
1. Start with an estimate
Choose a weight that seems appropriate based on previous sessions or general feel.
2. Assess after the set
Ask yourself how many repetitions you could still perform with good form. There’s a bit of a learning curve here, but you get used to it quickly.
3. Adjust
- If the set felt too easy, increase the load, the band tension, the difficulty of the position (based on the alternatives provided)
- If it felt too demanding, decrease slightly
The first set is often used to calibrate. Small adjustments between sets are expected, and it doesn’t have to be super precise right away. What matters is the intent you put into the effort, and into learning what “X RIR/RPE” feels like.
Examples
Program says: Biceps curl (dumbbell) 3×8 @ RIR 2
Each set should finish with about two repetitions left in reserve, with proper form.
- If you could do significantly more reps, increase the weight
- If you struggle to reach the target reps, reduce it slightly
Program says: Face pull (band) 3×8 @ RIR 1
Each set should finish with about one repetition left in reserve, with proper form and tension throughout the full range of motion.
- If you could do significantly more reps, take a step back, or switch to a thicker band.
- If you struggled, step forward or use a thinner band.
Program says: Plank 35-45s @ RPE 8
Each set should feel very hard, but you could keep going for another 10 or 15s.
- If it felt easy and you managed to do 45s, move to a more difficult variation (for example, plank shoulder taps)
- If you struggled to reach 30s, regress to an easier version (for example, on elbows or knees)
The alternatives will be provided in the program, you won’t have to guess. It usually takes a bit longer to learn what RPEs feel like, and it’s perfectly fine. Feedbacks and conversations help fine-tune it.
Understanding maximal effort (safely)
Accurately using RIR requires a sense of what “hard” actually feels like.
Occasionally reaching RIR 0 can help calibrate that perception, but it should be done under appropriate conditions.
Appropriate situations
- machine-based exercises
- controlled dumbbell movements
- bodyweight exercises
- stable and safe environments
Situations to avoid
- overhead lifts without a qualified spotter
- heavy barbell lifts performed alone
- technically demanding movements
- periods of high fatigue or discomfort
Safety guidelines
- stop immediately if pain appears
- maintain control throughout the set
- failure should occur from fatigue, not loss of form
- use this approach occasionally, not as a default
Most training should (and will) remain within RIR 1 to 3, and below RPE 10.
Common mistakes
Training to failure too often
Most of the benefits of training occur before failure. Staying slightly below maximal effort allows better recovery and technical consistency.
Underestimating effort
If all sets feel comfortable, the stimulus may be insufficient and you won’t progress as fast as you could.
Confusing discomfort with pain
Fatigue and effort are expected, pain is not. Learning the difference and keeping it under control is essential.
What this means for your training
This approach is used across most Desk Athletics programs. It is the first step before prescribing precise load progressions during weekly adjustments.
It allows training to:
- adapt to life constraints
- remain effective without precise load calculations
- progress consistently over time
It also helps you get a better sense of your effort levels. Most people have more reps in reserve than they think, which often means they can push a bit further than expected.
Being familiar with RIR/RPE gives you the keys to being autonomous in your training.
If you’d like to experience how this approach can work for you, reach out or schedule a discovery call.
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Aug. 2025
