Does lifting light or heavy weights give you the same muscle boost?
Similar improvements in skeletal muscle oxidative capacity after moderate (10-RM) and high repetition (20-RM) resistance training.
Not medical advice. For informational purposes only. Always consult a healthcare professional. Terms
Young men did leg workouts twice a week for six weeks, either with heavier weights (10 reps) or lighter weights (20 reps), both until muscles were too tired to continue. Scientists checked their muscle power, size, and energy systems.
Surprising Findings
High-rep resistance training improved muscle oxidative capacity more than moderate-rep training (-29.1% vs. -18.9%)
It contradicts the assumption that only aerobic exercise enhances mitochondrial function; here, even high-rep weight training significantly boosted muscle oxygen use.
Practical Takeaways
You can build muscle and improve metabolic health using either moderate (10-rep) or high (20-rep) sets, as long as you train to concentric failure.
Not medical advice. For informational purposes only. Always consult a healthcare professional. Terms
Young men did leg workouts twice a week for six weeks, either with heavier weights (10 reps) or lighter weights (20 reps), both until muscles were too tired to continue. Scientists checked their muscle power, size, and energy systems.
Surprising Findings
High-rep resistance training improved muscle oxidative capacity more than moderate-rep training (-29.1% vs. -18.9%)
It contradicts the assumption that only aerobic exercise enhances mitochondrial function; here, even high-rep weight training significantly boosted muscle oxygen use.
Practical Takeaways
You can build muscle and improve metabolic health using either moderate (10-rep) or high (20-rep) sets, as long as you train to concentric failure.
Publication
Journal
Journal of science and medicine in sport
Year
2025
Authors
Agustín Jerez-Martínez, José Manuel García de Frutos, S. Romero-Arenas
Related Content
Claims (6)
If you're lifting weights and go all the way to muscle failure, doing between about 6 and 35 reps per set can help you build muscle just as well as lower reps.
If you mix up your workout reps—sometimes doing just a few, sometimes a bunch—your muscles grow about as much as if you always stuck to the usual 8 to 12 reps per set.
Lifting weights twice a week for six weeks—whether doing fewer heavy reps or more lighter ones—can help young guys' muscles use oxygen better, which means their muscles may get more efficient at producing energy.
If young, healthy guys do leg workouts twice a week for six weeks, they get stronger — and doing lighter weights for more reps works about as well as heavier weights for fewer reps, except for hamstring curls, where more reps seem to help more.
Lifting weights twice a week for six weeks — whether using heavier or lighter weights — helps young, healthy guys build leg muscle just about the same amount, compared to not training at all.