Lifting light or heavy weights can make muscles bigger the same way
Divergent Strength Gains but Similar Hypertrophy After Low-Load and High-Load Resistance Exercise Training in Trained Individuals: Many Roads Lead to Rome.
Not medical advice. For informational purposes only. Always consult a healthcare professional. Terms
People who lifted light weights with lots of reps and others who lifted heavy weights with few reps both got stronger and their muscles grew bigger — but only for big movements like squats, not small ones like bicep curls.
Surprising Findings
Low-load training led to a -3% decrease in single-joint strength, while high-load improved it by 9%—despite both being done to failure.
Common fitness advice says 'training to failure' makes load irrelevant—but here, load still mattered for small muscles.
Practical Takeaways
If you can’t lift heavy, use light weights with 20–25 reps to failure for squats, lunges, and deadlifts—you’ll still build strength and size.
Not medical advice. For informational purposes only. Always consult a healthcare professional. Terms
People who lifted light weights with lots of reps and others who lifted heavy weights with few reps both got stronger and their muscles grew bigger — but only for big movements like squats, not small ones like bicep curls.
Surprising Findings
Low-load training led to a -3% decrease in single-joint strength, while high-load improved it by 9%—despite both being done to failure.
Common fitness advice says 'training to failure' makes load irrelevant—but here, load still mattered for small muscles.
Practical Takeaways
If you can’t lift heavy, use light weights with 20–25 reps to failure for squats, lunges, and deadlifts—you’ll still build strength and size.
Publication
Journal
Journal of applied physiology
Year
2025
Authors
K. Cumming, Ingrid Cecelia Elvatun, Richard Kalenius, Gordan Divljak, T. Raastad, N. Psilander, Oscar Horwath
Related Content
Claims (10)
For people who already lift weights, pushing to muscle failure with either light or heavy weights gives the same muscle growth and strength improvements after 12 weeks.
Whether you lift lighter weights or heavier weights until you can't do any more reps, both ways give you the same muscle growth and strength gains if you're already used to training.
Going all the way to failure on every set doesn’t really make you stronger than stopping a few reps short.
You can build muscle just as well lifting light weights as heavy ones — as long as you push yourself until you can’t do another rep.
When lifting lighter weights, pushing until you can't do any more reps helps build more muscle than stopping early. But with heavier weights, pushing to failure doesn't give much extra muscle growth compared to stopping a bit sooner.