Research
Adherence
Strength training adaptations are driven by neural factors early on, and muscle hypertrophy requires reaching muscular failure regardless of load, though high loads are needed for maximal strength gains.
To build muscle, you don't necessarily need to lift heavy weights. As long as you train close to muscular failure, lighter weights can build muscle just as effectively. However, if your goal is maximal strength, you still need to lift heavy loads.
StrongQualifiesVERY_HIGH confidence
In these studies, lifting a low load to positive failure produces equal hypertrophy to using a high load and fewer repetitions to reach failure (Mitchell et al. 2012; Ogasawara et al. 2013; Schoenfeld et al. 2015; Morton et al. 2016).
Why this rating
Cites multiple meta-analyses and studies showing equivalence in hypertrophy across loads when taken to failure.
Source
Adaptations to Endurance and Strength Training
David C. Hughes et al. · Cold Spring Harbor Perspectives in Medicine · 2017
narrative_reviewCited 525×
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