Mixed
In resistance-trained individuals, increasing proximity-to-failure (moving from 3-RIR to 1-RIR to Failure) linearly increases acute neuromuscular fatigue and negative perceptual responses, with males exhibiting greater fatigue than females when training to failure.
If you are resistance-trained, you do not need to train to absolute failure on every set. Stopping 1-3 reps before failure (RIR) significantly reduces acute neuromuscular fatigue and negative feelings (discomfort, soreness) compared to going to failure, while likely preserving similar training stimulus. This can improve your adherence and recovery, especially if you are male, as males showed greater fatigue at failure than females.
These findings support a linear relationship between RT proximity-to-failure and both acute neuromuscular fatigue and negative perceptual responses... acute neuromuscular fatigue increased as proximity-to-failure neared (FAIL > 1-RIR > 3-RIR) and was greater for males versus females when RT was performed to momentary muscular failure (FAIL).
Why this rating
Randomized crossover trial with resistance-trained subjects, though sample size is moderate (n=24) and duration is acute.
Source
Influence of Resistance Training Proximity-to-Failure, Determined by Repetitions-in-Reserve, on Neuromuscular Fatigue in Resistance-Trained Males and Females
Martin C. Refalo et al. · Sports Medicine - Open · 2023
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