Research
Mixed
High effort (proximity to failure) is a necessary condition for muscle hypertrophy, particularly when using low loads, whereas high-load training inherently generates high effort.
To build muscle, you must train with high effort, meaning you should stop 0-3 reps before you physically cannot complete another repetition. This is true whether you are lifting heavy weights or light weights. If you use light weights, you MUST go close to failure to get similar growth as heavy weights.
GoodSupportsHIGH confidence
Lasevicius et al. (2022, p. 346) determined significant quadriceps cross-sectional area increases within a 30% one-repetition maximum RT intervention only when sets were performed to momentary muscular failure and consequently '[...] conclude that when training with low loads, training with a high level of effort seems to have greater importance than total training volume in the accretion of muscle mass [...]'.
Why this rating
Supported by multiple citations (Fisher et al., Refalo et al., Robinson et al., Lasevicius et al.) within the review.
Source
What is resistance exercise? A review of current uses and potential ways forward
Lars Hubertus Lohmann et al. · European Journal of Applied Physiology · 2026
narrative_reviewCited 2×
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