Research

Mixed

Under volume-matched conditions, increasing resistance exercise training frequency from once per week to five times per week does not increase daily myofibrillar protein synthesis rates in young men.

If you are trying to build muscle, you do not need to train each muscle group every day. As long as you are doing the same total amount of work (volume) and lifting with sufficient intensity, training a muscle once a week will build muscle just as effectively as training it five times a week. Focus on getting your total reps and sets in, rather than worrying about frequency.

GoodRefutesHIGH confidence
Under the conditions of the present study, resistance exercise training frequency did not modulate daily myofibrillar protein synthesis rates in young men.
Brandon J. Shad et al. · International Journal of Sport Nutrition and Exercise Metabolism · 2021

Why this rating

Randomized crossover design with volume matching, though small sample size (n=9) and short duration (7 days).

Source

Daily Myofibrillar Protein Synthesis Rates in Response to Low- and High-Frequency Resistance Exercise Training in Healthy, Young Men

Brandon J. Shad et al. · International Journal of Sport Nutrition and Exercise Metabolism · 2021

DOI 10.1123/ijsnem.2020-0274

crossover · n=9Cited 6×
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DOI resolved against Crossref · corpus check 2026-06-10

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