
For size, each muscle needs a real stimulus about every 72 hours, so at least twice a week. Split it any way you like (full body twice, upper/lower, a split): the rule is the frequency, not the method. Each working set ends 1-3 reps from failure.
S Evidence: strong. Large trials or many studies, pointing the same way.
E Evidence: built from practice. What works for coaches and practitioners. Labelled that way.
Training a muscle twice a week grew more muscle than once a week, volume-equated (Schoenfeld, Ogborn & Krieger 2016, meta-analysis of 10 studies, 🟢) · the "72-hour rule": Andy Galpin (🟠) · see 136, 196, 197.
Not medical, legal or financial advice.
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