When lifting weights with a swinging motion instead of strict control, untrained people can lift more total weight, but this does not lead to bigger muscles. This suggests that how much tension is...
Mechanism
Synthesis from 1 study
Swinging weights moves more total mass, but the muscles aren’t pulled hard or long enough to trigger growth. Muscle growth needs steady, strong tension — not just heavy lifting — and momentum cuts that tension short, so the muscle doesn’t respond by getting bigger.
Most probable mechanism
When you swing weights instead of lifting them slowly, the muscle doesn't stay under steady pull for long enough, so it doesn't get the signal to grow, even though you're moving more weight overall.
Externally applied momentum reduces the duration and magnitude of tension applied to muscle fibers during the concentric and eccentric phases of contraction
Lower mechanical tension decreases activation of mechanosensitive signaling pathways within muscle cells, including those involving mTOR and focal adhesion kinase
Reduced signaling leads to diminished rates of myofibrillar protein synthesis and impaired muscle fiber remodeling
Evidence from Studies
Supporting (1)
Community contributions welcome
Do Cheaters Prosper? Effect of Externally Supplied Momentum During Resistance Training on Measures of Upper Body Muscle Hypertrophy
Contradicting (0)
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