Mixed
Single-set resistance training performed to 2 repetitions in reserve (RIR-2) produces similar gains in muscular strength and local muscular endurance compared to training to failure (FAIL) in resistance-trained individuals.
If you are already trained, you do not need to train to failure on every set to build strength or muscle. Stopping your sets with 2 reps left in the tank (RIR-2) yields the same strength and endurance results as going to failure, while likely feeling better and allowing for better recovery. This makes training more sustainable and time-efficient.
Increases in strength and local muscular endurance were similar between conditions.
Why this rating
Randomized controlled trial with pre-registration, blinded outcome assessors, and Bayesian analysis, though sample size is moderate (n=42).
Source
Without fail: Muscular adaptations in single set resistance training performed to failure or with repetitions-in-reserve
Tom Hermann et al. · 2024
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