Mixed
In strength-trained individuals, resistance training frequency (1x vs 3x per week) produces equivalent maximal strength (1RM) and muscle hypertrophy (CSA) gains when total training volume is equalized.
If you are an experienced lifter, you do not need to train a muscle group three times a week to get bigger or stronger. You can train it once a week, provided you perform the same total amount of work (volume) and intensity. Focus on getting your sets in during that single session rather than spreading them out for frequency's sake.
RT performed three times a week showed similar increases in 1RM and CSA to the program performed once a week, regardless of training volume equalization.
Why this rating
High-quality within-subject design with trained population, though limited to one exercise.
Source
Effect of different training frequencies on maximal strength performance and muscle hypertrophy in trained individuals—a within-subject design
Ricardo Pereira Neves et al. · PLoS ONE · 2022
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