The Study
The effect of eccentric phase duration on maximal strength, muscle hypertrophy and countermovement jump height: A systematic review and meta-analysis
This study looked at lots of other studies about how slowly lowering weights affects strength and jumping. It found some patterns, like shorter slow lowers might help you jump higher. But it didn't do the experiments itself — it just combined results from others, so we can't be 100% sure.
Analysis score
Maximum 85 for a systematic review with meta-analysis.
Where the score came from
This study looked at whether lifting weights slowly or quickly when lowering them affects strength, muscle growth, and jumping ability.
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 544 / 100
Quality score
Systematic reviews and meta-analyses of cohort studies. They sit above a single cohort study but below a single randomized trial, because the underlying evidence is still observational.
Key takeaways
Summary
Based on the study abstract and findings.
- 1Jumping higher matters for athletes; getting stronger matters for lifters.
- 2Muscle size didn’t change much either way.
- 3Faster lowering improved jump height by g = −0.73.
- 4Slower lowering helped strength gain by g = 0.33.
- 5Muscle growth showed almost no difference (g = 0.05).
Score breakdown, methodology, conflicts of interest, evidence analysis & raw study data
Publication
Journal
Journal of Sports Sciences
Year
2025
Authors
C. H. Amdi, Andrew King
Related Content
Claims (4)
When the total amount of weight lifted is the same, changing how slowly you lower the weight during resistance training does not change how much muscle grows.
In trained athletes, performing the lowering phase of resistance exercises more quickly increases the height of a countermovement jump by a meaningful amount.
Among experienced weightlifters who perform the same total training volume, longer lowering phases in resistance exercises are linked to equal or greater increases in maximum strength compared to shorter lowering phases.
Changing how long the lowering phase of a weightlifting movement lasts does not meaningfully affect muscle growth in people who regularly train.
Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.