Research

Mixed

Resistance-trained individuals achieve similar quadriceps muscle hypertrophy after eight weeks of resistance training when terminating sets with 1-2 repetitions in reserve (RIR) compared to terminating sets at momentary muscular failure.

If you are experienced with resistance training, you do not need to train to absolute failure on every set to build muscle. Stopping your sets with 1-2 reps left in the tank (RIR) produces the same muscle growth as going to failure over an 8-week period. This approach likely allows you to recover faster and maintain better form, as failure training induces significantly higher acute fatigue and repetition loss.

GoodSupportsHIGH confidence
Increases in quadriceps thickness (average of RF and VL) from pre- to post-intervention were similar for FAIL [0.181 cm (HDI: 0.119 to 0.243)] and RIR [0.182 cm (HDI: 0.115 to 0.247)].
Martin C. Refalo et al. · Journal of Sports Sciences · 2024

Why this rating

Randomized controlled trial with resistance-trained participants, though sample size is small (n=18) and duration is short (8 weeks).

Source

Similar muscle hypertrophy following eight weeks of resistance training to momentary muscular failure or with repetitions-in-reserve in resistance-trained individuals

Martin C. Refalo et al. · Journal of Sports Sciences · 2024

DOI 10.1080/02640414.2024.2321021

rct · n=18Cited 21×
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DOI resolved against Crossref · corpus check 2026-06-10

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