Mixed
Higher intensity resistance training (60-80% 1RM) is superior to lower intensities (20-40% 1RM) for maximizing long-term strength gains, although all intensities increase strength in beginners.
If your main goal is to get as strong as possible, you should eventually incorporate heavier weights (60-80% 1RM). While lighter weights (20-40% 1RM) will help you get stronger, especially in the first few weeks, they will not help you maximize your strength potential as effectively as heavier weights. For general fitness and muscle growth, moderate weights are sufficient and may be easier on your joints.
However, if maximizing strength gains over the long-term training is a primary goal, it is necessary employ higher training intensities.
Why this rating
RCT with within-subject design, clear statistical differentiation between high and low intensity groups for strength at 12 weeks.
Source
Effects of different intensities of resistance training with equated volume load on muscle strength and hypertrophy
Thiago Lasevicius et al. · European Journal of Sport Science · 2018
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