The Study
Lengthened partial repetitions elicit similar muscular adaptations as full range of motion repetitions during resistance training in trained individuals
This study is like a fair race between two ways of lifting weights — one with full arm movement and one with half. It found that both ways made people’s arm muscles grow about the same. So we can say they’re equally good for this group, but we don’t know if it works the same for everyone else.
Analysis score
Maximum 90 for a randomized controlled trial.
Where the score came from
This study tested whether doing partial weightlifting moves that stretch the muscle (like half-deadlifts) work as well as doing full moves (like full deadlifts) for building muscle and endurance.
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 567 / 100
Quality score
Participants are randomly assigned to treatment or control groups, minimizing bias. The gold standard for testing whether an intervention causes an effect.
Key takeaways
Summary
Based on the study abstract and findings.
- 1Yes — you don’t need to move through the full range to get the same muscle growth; just getting the muscle stretched is enough.
- 2Both methods grew muscles and improved endurance by the same amount after 8 weeks of training.
Score breakdown, methodology, conflicts of interest, evidence analysis & raw study data
Publication
Journal
PeerJ
Year
2025
Authors
Milo Wolf, Patroklos Androulakis Korakakis, A. Piñero, Adam E. Mohan, Thomas Hermann, Francesca Augustin, M. Sapuppo, Brian Lin, Max Coleman, Ryan Burke, Jeff Nippard, P. Swinton, B. Schoenfeld
Related Content
Claims (10)
In trained individuals, lifting weights through partial ranges of motion or at longer muscle lengths produces the same amount of muscle growth as lifting through full ranges of motion.
When trained people lift weights using either a partial range of motion at long muscle lengths or a full range of motion, and both methods use the same total workload and effort, the amount of muscle growth is the same.
If you're already fit, doing bicep and tricep exercises through a shorter range of motion—but pushing to your max—can build muscle just as well as doing full reps.
For people who are already trained, lifting weights with muscles stretched out does not result in more muscle growth than lifting with muscles shortened, and it does not result in less muscle growth than lifting through a full range of motion.
When people lift weights through a full motion vs. just part of the motion, the muscles might look like they grow more in one case—but that could just be because the weight feels heavier at different points, not because the muscle is stretched more. So we can’t be sure if stretching the muscle is what’s causing the growth.
Doing only the bottom part of an exercise (where the muscle is stretched) can build as much muscle in your arms and legs as doing the full movement, as long as you put in the same amount of effort and work.
Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.