The Study
The Effect of Resistive Exercise Rest Interval on Hormonal Response, Strength, and Hypertrophy With Training
This study looked at two groups of guys doing weight training with different rest times and saw that one group got a little bigger arms — but we don’t know if the rest time actually caused it, because we can’t be sure they were randomly assigned. So all we can say is: maybe longer rests helped, maybe not.
Analysis score
Maximum 90 for a randomized controlled trial.
Where the score came from
Two groups lifted weights with different rest times. One group rested 1 minute, the other 2.5 minutes. At first, the short-rest group had more stress hormones, but that faded. After 10 weeks, the long-rest group’s arms grew more, but both groups got equally strong.
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 537 / 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 — longer rests led to noticeably bigger arms, even though strength gains were the same.
- 2Arm size increased by 12.3% with 2.5-minute rests vs.
- 35.1% with 1-minute rests.
- 4Strength improved similarly in both groups.
Score breakdown, methodology, conflicts of interest, evidence analysis & raw study data
Publication
Journal
Journal of Strength and Conditioning Research
Year
2009
Authors
R. Buresh, K. Berg, J. French
Related Content
Claims (5)
Longer breaks between sets during weight training allow for more total weight to be lifted, which increases the mechanical stress on muscles and may promote greater muscle growth.
When you lift weights and rest only 1 minute between sets, your body releases more stress and sex hormones right after the workout — but only at the very start; after a few weeks, this effect goes away.
If you rest longer between weightlifting sets (2.5 minutes instead of 1 minute), your arms grow bigger over 10 weeks — even if your strength doesn’t change.
Whether you rest 1 minute or 2.5 minutes between sets, your strength gains in squat and bench press end up being about the same after 10 weeks of training.
Even if your hormones spike a lot right after your first few workouts, that doesn’t mean you’ll grow more muscle or get stronger later on.
Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.