The Study
Exercise Selection Differentially Influences Lower Body Regional Muscle Development
This study is like testing two different ways to grow your leg muscles by having each leg do a different workout. It found that one kind of exercise might make one part of your thigh bigger, and another kind might make a different part bigger. But we can’t say it works the same for everyone — just for these 30 people who already lift weights.
Analysis score
Maximum 90 for a randomized controlled trial.
Where the score came from
Some exercises make one part of your muscle grow more than another — like how leg extensions puff up the front of your thigh, but leg presses puff up the side.
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 561 / 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 — choosing the right exercise can target specific muscle regions for better shaping or performance in under 2 months.
- 2Rectus femoris: +91–99% chance bigger with leg extensions.
- 3Vastus lateralis: +88–99% chance bigger with leg presses.
- 4Medial gastrocnemius: +99% chance bigger with straight-leg toe press.
- 5Lateral gastrocnemius & soleus: no difference.
Score breakdown, methodology, conflicts of interest, evidence analysis & raw study data
Publication
Journal
Journal of Science in Sport and Exercise
Year
2024
Authors
Ryan Burke, A. Piñero, Adam E. Mohan, Thomas Hermann, M. Sapuppo, Francesca Augustin, Max Coleman, P. Korakakis, Milo Wolf, P. Swinton, B. Schoenfeld
Related Content
Videos (2)
Claims (7)
When trained individuals exercise biarticular muscles with their joints in positions that stretch the muscles more, those muscles grow larger than when exercised in positions where the muscles are less stretched.
Doing leg extensions (kicking your leg out while sitting) makes the front thigh muscle right above your knee grow more than doing leg presses (pushing a heavy platform with both legs).
Pushing a heavy leg press machine makes the outer part of your thigh muscle grow more than doing leg extensions, because it puts more overall stress on that part of the muscle.
Doing calf raises with your knees straight (standing on toes) makes the inner part of your calf muscle grow more than doing them with your knees bent (seated), because the muscle is stretched more.
The outer part of your calf and the deeper calf muscle don’t grow better with either straight-knee or bent-knee calf raises — they respond similarly to both.
Not all parts of your thigh and calf muscles grow the same way — some parts grow better with certain exercises, so doing different types of lifts can help you build muscle more evenly.
Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.