How long should a workout be?
As long as your sets take, which for most people is 45 to 75 minutes, because the sets per muscle decide the result, not the clock.
Work backwards from the sets. Ten to twenty hard sets per muscle per week, spread over two sessions, is roughly six to ten sets per muscle per session. With two to three minutes of rest, that lands between 45 and 75 minutes.
If you have less time, the fix is not shorter rest, because that costs you reps. Pair exercises that do not compete, like a row between sets of squats, or cut the exercises and keep the sets.
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Sources
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- Pelland, J.C. et al. (2025). The resistance training dose response: meta-regressions exploring the effects of weekly volume and frequency on muscle hypertrophy and strength gains. Sports Med. Weekly sets per muscle drive the result, so session length follows from how you spread those sets.
- Schoenfeld, B.J. et al. (2016). Longer interset rest periods enhance muscle strength and hypertrophy in resistance-trained men. J Strength Cond Res 30(7). Resting three minutes beat one minute, which is most of why sessions run long.
- Burke, R. et al. (2024). Less time, same gains: comparison of superset vs traditional set training on muscular adaptations. SportRxiv preprint. 43 trained adults, 8 weeks: pairing exercises gave the same growth and strength in 36% less time.