For men who already train regularly, doing resistance workouts once or twice a week with the same total workload as more frequent sessions results in similar gains in muscle size and strength.
Mechanism
Synthesis from 1 study
Lifting weights makes your muscles start repairing and growing, and that process keeps going for a day or two after each workout. If you do the same total amount of lifting but only once a week instead of twice, your muscles still have enough time to grow just as much — so you don’t lose gains by...
Most probable mechanism
When you lift weights, your muscles start making new proteins to repair and grow. This process stays active for a day or two after each workout. If you do the same total amount of lifting but spread it over fewer days, your muscles still get enough time between sessions to keep building muscle and getting stronger, so you don’t lose progress.
Resistance training triggers an increase in muscle protein synthesis rates that remains elevated for 24–48 hours post-exercise.
When training volume is equated across frequencies, the cumulative protein synthesis over the week is similar regardless of whether sessions occur once or twice weekly.
Sustained net muscle protein balance over time leads to comparable hypertrophy and strength gains despite reduced session frequency.
Evidence from Studies
Supporting (1)
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Effects of equal-volume resistance training with different training frequencies in muscle size and strength in trained men
Contradicting (0)
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