When lifting weights with slow, controlled movements—10 seconds up and 4 seconds down—muscle growth is lower than when using faster, standard tempos of 1–2 seconds up and 1–2 seconds down, provided...
Strongly contradicted
Multiple high-quality studies challenge this claim.
Not medical advice. For informational purposes only. Always consult a healthcare professional.
When lifting weights with slow, controlled movements—10 seconds up and 4 seconds down—muscle growth is lower than when using faster, standard tempos of 1–2 seconds up and 1–2 seconds down, provided...
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Deliberately slow concentric and eccentric tempos (10 seconds lift, 4 seconds lower) reduce muscle hypertrophy compared to standard tempos (1–2 seconds lift, 1–2 seconds lower) when training volume and effort are matched.
When lifting and lowering weights very slowly, each repetition takes longer but the force your muscles generate during each movement is lower. This means your muscle fibers don't experience enough strong tugging to trigger the signals that tell them to grow bigger. Even though you're doing the same total work, the weaker pulls during each slow movement don't activate the growth machinery as effectively as the sharper, stronger pulls from faster movements.
What the research says
Supports
0 studies
Contradicts
1 study
Study: Effects of resistance training on hypertrophy, strength and tensiomyography parameters of elbow flexors: role of eccentric phase duration
This study provides evidence contradicting the claim.
Score breakdown, mechanism chain, raw evidence, ideal studies needed & 1 supporting studies