The Claim
In resistance-trained men, 8 weeks of volume-matched unilateral leg extensions performed with either fast (1-0-1) or slow (1-0-3) eccentric tempo result in similar increases in proximal quadriceps muscle thickness (approximately 3–4%) and maximal strength (17–22%), indicating no significant difference in muscle growth or strength gains between the two eccentric tempos.
What the research says
Supports is higher
Support is ahead, but a single strong opposing study can change this.
These are independent scores, not a percentage. Higher-grade studies count more, so a single strong opposing study can outweigh several weaker ones.
In men who regularly lift weights, performing leg extensions with a fast or slow lowering phase for 8 weeks leads to the same amount of muscle thickening in the upper thigh and the same increase in maximum strength.
See the scientific wording
In resistance-trained men, 8 weeks of volume-matched unilateral leg extensions with either fast (1-0-1) or slow (1-0-3) eccentric tempo produce similar increases in proximal quadriceps muscle thickness (≈3–4%) and maximal strength (17–22%), indicating that eccentric tempo does not significantly influence overall muscle growth or strength gains in this context.
When muscles are stretched under load, the force on muscle fibers triggers signals that turn on protein building, and this happens just as much whether the muscle is lowered quickly or slowly — so the muscle grows and gets stronger the same either way.
What the research says
1 studyFor guys who lift weights, doing leg extensions with a slow or fast lowering motion for 8 weeks led to almost the same amount of muscle growth in the upper thigh and strength gain — so it doesn’t really matter which speed you pick.
Score breakdown, mechanism chain, raw evidence, ideal studies needed & 1 supporting studies
Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.