Research

Hormonal

Low-load resistance training (40% 1RM) performed to failure produces significant muscle hypertrophy and strength gains regardless of whether rest intervals are short (30s) or long (150s).

You do not need to rush your rest periods when using lighter weights (40% of your max). Whether you rest 30 seconds or 2.5 minutes between sets, as long as you take the set to failure, your muscle growth and strength gains will be the same. Use the rest time that allows you to maintain good form and feel less fatigued.

ModerateSupportsMEDIUM confidence
our results suggest that acute hormonal responses, as well as chronic changes in muscle hypertrophy and strength in low load training to failure are independent of the rest interval length.
Julius Fink et al. · Juntendo Medical Journal · 2018

Why this rating

Small sample sizes (n=14 acute, n=21 longitudinal), short duration (8 weeks), and lack of a high-load control group limit generalizability.

Source

Acute and Long-term Responses to Different Rest Intervals in Low Load Resistance Training

Julius Fink et al. · Juntendo Medical Journal · 2018

DOI 10.14789/jmj.2018.64.jmj18-p66

rct · n=21
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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