Mixed
High-load resistance training (80% 1RM) produces greater neural adaptations and strength gains than low-load training (30% 1RM) despite inducing similar muscle hypertrophy.
If your goal is to get stronger, you must lift heavy weights (around 80% of your max). While lifting lighter weights (30% of max) to failure will build muscle size just as well, it will not make you as strong because it fails to train your nervous system to recruit muscle fibers efficiently. To maximize strength, prioritize high-load training.
Despite eliciting similar hypertrophy, 80% 1RM improved muscle strength more than 30% 1RM, and was accompanied by increases in VA and EMG amplitude during maximal force production. Furthermore, training at 80% 1RM resulted in a decreased neural cost to produce the same relative submaximal torques after training, whereas training at 30% 1RM did not.
Why this rating
Randomized controlled trial with clear group separation and objective neuromuscular measures, though sample size is modest (n=26).
Source
Greater Neural Adaptations following High- vs. Low-Load Resistance Training
Nathaniel D.M. Jenkins et al. · Frontiers in Physiology · 2017
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