Among trained young men doing the same total amount of weight training, switching from working out twice a week to once a week was linked to a small increase in bicep muscle thickness, but no change...
Mechanism
Synthesis from 1 study
When people who already lift weights train their arms less often, their muscles get more time to recover between sessions. This longer rest keeps the body’s muscle-building signals active longer, so a little more muscle grows—but not enough to make them stronger.
Most probable mechanism
When someone who already lifts weights trains less often, their muscles stay under stress for longer between sessions, which keeps a key growth signal turned on longer. This lets the body build more muscle protein over time, leading to slightly thicker muscles without making them stronger.
Reduced training frequency extends the duration of muscle protein breakdown and recovery phase between sessions
Prolonged recovery period sustains elevated phosphorylation of mTORC1 pathway components in skeletal muscle
Sustained mTORC1 signaling increases ribosomal biogenesis and translation initiation, enhancing net muscle protein synthesis
Increased net protein synthesis over time leads to modest myofiber hypertrophy without altering maximal force production capacity
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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Gold Standard Evidence Needed
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