The Study
Effects of Resistance Training Frequency on Measures of Muscle Hypertrophy: A Systematic Review and Meta-Analysis
This study combines results from several experiments to see if working out muscles more often helps them grow bigger. It shows that working out more frequently is linked to bigger muscles, but because we don't know exactly how the original experiments were set up, we can't say for sure that working out more causes the growth. It's like seeing a pattern, but not having all the pieces to prove it's the only reason.
Analysis score
Maximum 100 for a systematic review with meta-analysis.
Where the score came from
This review looked at multiple studies to see how many times per week you should work out the same muscles to build the most size.
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 538 / 100
Quality score
The highest quality evidence. Systematic reviews and meta-analyses that pool randomized controlled trials, giving the most reliable summary of experimental evidence.
Key takeaways
Summary
Based on the study abstract and findings.
- 1Yes, training a muscle group twice weekly appears to be better for muscle growth than once weekly, but there is not enough data to know if training three times a week is even better.
- 2Training muscles twice a week led to better growth than once a week.
- 3Higher frequency training showed a larger effect size (0.49) compared to lower frequency (0.30).
Score breakdown, methodology, conflicts of interest, evidence analysis & raw study data
Publication
Journal
Sports Medicine
Year
2016
Authors
B. Schoenfeld, Daniel I. Ogborn, J. Krieger
Related Content
Claims (4)
If you do the same total amount of weightlifting work each week, doing it all in one session will build your muscles just as much as spreading those workouts across multiple days.
Doing resistance training more often seems to help build more muscle compared to training less often. Research indicates that people who lift weights more frequently experience significantly better muscle growth results than those who train less often.
We don't currently have enough proof to say whether working out a specific muscle group three times a week builds more muscle than doing it twice a week. Because the research isn't clear on this, experts can't yet recommend training muscles more than twice weekly for growth.
If you work out the same total amount, splitting your muscle workouts to hit each group twice a week builds more muscle than doing it all in one day a week. Basically, spreading out your training leads to better muscle growth.
Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.