RIR (reps in reserve)
Reps in reserve — how many more repetitions you could have completed when you racked the set. RIR 0 is failure; RIR 2 means two were still there. It is the simplest way to prescribe effort without relying on percentages of a maximum that shifts from week to week. Most hypertrophy work lives between RIR 0 and RIR 3.
In practice
Prescribing 3×8 at RIR 2 means: pick a load where, at the eighth rep, you would still have two left. If the set ends and it feels like five were left, the load was too light; if you failed on the seventh, it was too heavy. The following week you adjust the load, not the number.
How to use it in a plan
Use RIR to set the intensity of each set and let the load follow. A typical block starts around RIR 3 and tightens to RIR 1 in the last weeks before the deload. In NoteFit, RIR is written next to the reps in each exercise’s free-text field.
FAQ
RIR or a percentage of my max?
RIR adapts to the day; a percentage assumes your max is today’s, which it rarely is. For hypertrophy, RIR is usually more practical and needs no max testing.
Can I estimate RIR accurately?
At first almost everyone underestimates — beginners think they have two left when they have five. It improves with practice, and with the occasional set taken to failure to calibrate.