Using RIR and RPE without testing your max

1.The problem with percentages

Prescribing "4×6 at 80% of max" looks precise, but it rests on a number measured on one day that stopped being true the next. A max climbs across a block, drops after a week of bad sleep, and moves with room temperature and time of day.

Testing a max also costs a whole session and some fatigue, and for hypertrophy it adds nothing. For anyone who does not compete, max testing is a cost with no return.

2.RIR: counting what was left

RIR is reps in reserve: how many more you could have done when you closed the set. RIR 0 is failure, RIR 2 means two were still there. It is a count, not a vague feeling.

The prescription reads like this: "3×8 at RIR 2" means picking a load where, at the eighth rep, two would still be left. If the set ends with five left, the load was light; if you failed on the seventh, it was heavy. The adjustment is always to the load, never to the rep number that was written down.

3.RPE: the same thing read backwards

RPE is an effort scale from 1 to 10. In the version used in strength training it reads as the inverse of RIR: RPE 10 is failure, RPE 9 is one rep in reserve, RPE 8 is two, RPE 7 is three.

It does the same job but communicates better between coach and athlete, because a number on the scale does not force a conversation about absolute loads. Two athletes of different strength do "4×6 @ RPE 8" with different weights and the same relative stimulus.

4.Spreading the effort across a block

Start the mesocycle loose and tighten at the end. A simple four-week progression: RIR 3 in week one, RIR 2 in week two, RIR 1 in week three, RIR 1 or 0 on the last exercises of week four, and a deload in week five.

The load rises by itself under this logic. If reps stay the same and RIR comes down, you have to put more weight on the bar to reach the same number — progression is baked into the prescription instead of being a weekly decision.

5.Where to tighten and where to leave room

On heavy compound lifts — squat, bench, overhead press — it pays to leave one or two reps in reserve almost always. Failure on these costs a lot of fatigue, needs a spotter, and is where technique breaks down first.

On isolation work and machines, going near failure is safe and is where RIR 0 or 1 pays off most. A triceps extension taken to failure does not cost you the week; a squat taken to failure does.

6.Calibrating the estimate

Almost everyone underestimates RIR at first: they think two are left when five are. Calibration comes from taking a set to failure now and then, on a safe isolation exercise, and comparing it with what you had estimated.

With practice the error closes. Until it does, assume you are further from failure than you think and pick the load accordingly — that is the cheaper mistake.

7.Writing this into a plan

In NoteFit, RIR or RPE goes next to the reps, in each exercise’s free-text field: "8-10 · RIR 2". The example plan in these guides uses exactly that format on one of the exercises in the second upper session.

Everything else stays the same: sets still count towards the muscle’s weekly volume, with or without RIR written beside them. Effort says how close to failure each set goes; volume says how many sets the muscle received.

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