The Study
When duration matters: rethinking resistance training load through time under tension
This article is like someone saying, 'I think if you move slower during push-ups, your muscles might grow better' — but they didn’t do any experiments to prove it. So we can’t say it’s true, just that someone has an idea.
Analysis score
Maximum 0 for a editorial/opinion.
Where the score came from
This article says that how long your muscles are working during exercise matters just as much as how heavy the weight is. Slowing down the lowering part of a lift makes muscles work harder and repair more, while speeding up the lifting part can make you stronger faster. Even if you use light weights, if you make your muscles work longer, you can still grow and get stronger.
Where does this study sit?
Reviews of RCTs (Meta-analyses)
Max 100Randomized Trials
Max 90Reviews of Cohort Studies
Max 85Cohort Studies
Max 72Reviews of Case-Control Studies
Max 63Case-Control Studies
Max 58Cross-Sectional & Case Series
Max 50Expert Opinion
Max 50 / 100
Quality score
Based on clinical experience or non-systematic literature reviews. The lowest level of evidence as they are most susceptible to bias and personal perspective.
Key takeaways
Summary
Based on the study abstract and findings.
- 1Yes — this means most people can stick to a plan that uses slower movements to build muscle without heavy weights, which is helpful for older people or those recovering from injury.
- 2About 70% of reps are done at the right speed, even when tired.
Score breakdown, methodology, conflicts of interest, evidence analysis & raw study data
Publication
Journal
Revista Brasileira de Cineantropometria & Desempenho Humano
Year
2025
Authors
E. de Souza Bezerra
Related Content
Claims (10)
Lifting weights makes your muscles grow because the longer and harder you work them, the more they get the signal to build new muscle fibers.
Muscle growth occurs primarily when mechanical tension is applied over a sustained period of time.
Your muscles grow bigger mainly because of how much total force they feel over time—not whether you do your workouts all at once or spread out over the week.
Lifting weights fast or slow doesn’t make much difference in how much your muscles grow — the extra gain from going slow is practically nothing.
Performing the upward phase of weightlifting movements more quickly can lead to higher power output than performing the same movements slowly.
During resistance training, about 70% of lifts are performed at the planned speed, even when fatigue causes natural changes in movement tempo, suggesting that training programs based on controlling time under tension remain practical and feasible.
Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.