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Expert consensusRest intervals
A position stand on progression models recommends that intermediate and advanced lifters use a wider loading range with eventual emphasis on heavy loading, taken with 3 to 5 minute rest periods between sets at a moderate contraction velocity.
How Fibral applies it: Give an intermediate or advanced lifter 3 to 5 minutes between heavy sets of a priority lift rather than the shorter rests that suit accessory work. This is not encoded: it rests on a position stand, and rest-compound-minimum states the same metric for the same target from a randomised trial. Stronger evidence wins whatever the audience, so encoding this would let an opinion displace a trial. Superseded by curated-rest-intervals-hypertrophy until a trial on heavy-set rest is acquired.
Limits and applicability
No limitation statement has been published for this note yet. Treat it as a general evidence-informed rule, not an individualized guarantee.
- American College of Sports Medicine. (2009). American College of Sports Medicine position stand. Progression models in resistance training for healthy adults. View source
Approved content v1 · updated Aug 17, 2026
Meta-analysisRest intervals
A systematic review with Bayesian meta-analysis of inter-set rest and hypertrophy found a small hypertrophic benefit to rest intervals longer than 60 s, probably mediated by preserved volume load. It detected no appreciable further difference in hypertrophy beyond 90 s.
How Fibral applies it: Rest more than 60 s between sets when size is the goal, and expect no further hypertrophy return from resting past 90 s. Neither number is encoded as a bound: "no further benefit past 90 s" is not a ceiling, and a floor alone cannot compile because the maximum for this metric is scientific policy and has to come from a paper. The direction is carried by rest-hypertrophy-longer-preference instead.
Limits and applicability
No limitation statement has been published for this note yet. Treat it as a general evidence-informed rule, not an individualized guarantee.
- Singer A, Wolf M, Generoso L, Arias E, Delcastillo K, Echevarria E, Martinez A, Androulakis Korakakis P, Refalo MC, Swinton PA, Schoenfeld BJ. (2024). Give it a rest: a systematic review with Bayesian meta-analysis on the effect of inter-set rest interval duration on muscle hypertrophy View source
Approved content v1 · updated Aug 17, 2026
Randomized trialRest intervals
A systematic review of inter-set rest concluded that both short and long rest can build muscle, and that in trained participants measured sensitively the evidence leans toward long rest - the reviewed trials split short from long at 60 seconds. Shorter rest is more time-efficient but can reduce the work completed in later sets.
How Fibral applies it: Default to inter-set rest well beyond the 60-second mark on multi-joint lifts; shorten it deliberately only when trading a small amount of volume for time.
Limits and applicability
No limitation statement has been published for this note yet. Treat it as a general evidence-informed rule, not an individualized guarantee.
- Grgic J, Lazinica B, Mikulic P, Krieger JW, Schoenfeld BJ (2017). The effects of short versus long inter-set rest intervals in resistance training on measures of muscle hypertrophy: A systematic review View source
Approved content v4 · updated Aug 17, 2026
Randomized trialRest intervals
A controlled trial in resistance-trained men found that resting 3 minutes between sets produced greater strength and muscle thickness gains than resting 1 minute, because longer rest preserved the volume-load completed in subsequent sets. Very short rest can compromise the total work performed.
How Fibral applies it: Rest about 2-3 minutes between sets of demanding compound exercises so later sets keep their reps and load; short rest is acceptable for small isolation work.
Limits and applicability
No limitation statement has been published for this note yet. Treat it as a general evidence-informed rule, not an individualized guarantee.
- Schoenfeld BJ, Pope ZK, Benik FM, Hester GM, Sellers J, Nooner JL, Schnaiter JA, Bond-Williams KE, Carter AS, Ross CL, Just BL, Henselmans M, Krieger JW (2016). Longer Interset Rest Periods Enhance Muscle Strength and Hypertrophy in Resistance-Trained Men View source
Approved content v4 · updated Aug 17, 2026