The Study
Effect of different training frequencies on maximal strength performance and muscle hypertrophy in trained individuals—a within-subject design
This study found that lifting weights once a week or three times a week made muscles stronger and bigger in a similar way — but only if you lifted the same total amount of weight. If you lifted more total weight with three times a week, you got a little more benefit. But we can’t say for sure that the frequency itself caused the change — maybe something else did.
Analysis score
Maximum 90 for a randomized controlled trial.
Where the score came from
Two legs trained differently: one leg worked once a week, the other three times—but total weight lifted was either the same or different. Both legs got stronger and bigger, but only when the three-times-a-week leg lifted more total weight did it gain noticeably more.
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 554 / 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—lifting more total weight matters more than spreading it across more days.
- 2Both legs got stronger and bigger.
- 3When total weight was equal: no difference.
- 4When three-times-a-week leg lifted more: +0.51 strength gain, +0.63 muscle growth (medium effects).
Score breakdown, methodology, conflicts of interest, evidence analysis & raw study data
Publication
Journal
PLoS ONE
Year
2022
Authors
R. P. Neves, Felipe C. Vechin, E. Teixeira, D. D. da Silva, C. Ugrinowitsch, H. Roschel, A. Aihara, V. Tricoli
Related Content
Claims (10)
Your muscles grow bigger mainly because of how much total force they feel over time—not whether you do your workouts all at once or spread out over the week.
If you lift weights the same total amount each week, it doesn’t matter if you do it in one big session or split into three smaller ones—you’ll get just as strong and build just as much muscle.
If you do the same workout three times a week instead of once, and you end up doing more total weight lifted, you’ll get stronger and build more muscle—because you’re doing more work overall.
If you do leg presses for 9 weeks, your legs will get stronger and bigger—even if you do it once or three times a week.
If you train your legs with the leg press machine for 9 weeks, you’ll get stronger and your thighs will get bigger—even if you do it just once a week or spread it out over three days.
When you do more total weight lifting, you get stronger and bigger muscles—whether you do it in one day or spread it out. Just doing more sessions doesn’t help unless you’re lifting more overall.
Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.