Guide

How long should a workout be

There's no correct workout length — there's a number of hard sets and the rest between them. Count those and the time follows. Usually it's 45–75 minutes.

Updated October 16, 2026

Time is sets plus rest

A workout has three parts: the warm-up, the working sets and the rest between them. A set lasts 30–60 seconds; rest runs from one to three minutes. So one working set with its rest is 1.5–4 minutes, and you spend most of your gym time resting.

That gives a simple sum: 15 working sets at 2.5 minutes each is about 40 minutes, plus 10 minutes of warm-up — 50. 25 sets is already more than an hour. So "how long should I train" is really "how many sets should I do".

How many sets you need per workout

For muscle growth what matters is weekly volume — hard sets per muscle per week. If you need 10–15 sets for each major group and train three times, that's 15–25 sets per workout. That's 45–75 minutes.

More sets give more growth, but with diminishing returns (Schoenfeld, Ogborn, Krieger, 2017). And the last sets of a long workout are usually worse: fatigue builds and the weights drop. If a workout drifts toward two hours, it's usually better to split it in two than to finish it exhausted. See how many sets per session different splits give.

Rest takes the most time

Short rest shortens the workout, but it also eats reps. In Schoenfeld et al. (2016), three minutes of rest gave trained men more growth and strength than one minute. In a newer review by Singer et al. (2024), going past 90 seconds added little for growth — but didn't hurt either.

In practice: 2–3 minutes on heavy compounds, 60–90 seconds on isolation. Rest without a timer is almost always longer than it feels, especially with a phone in your hand. Set the rest timer — it's the easiest way to finish in an hour without losing quality.

How to cut a workout without losing work

Antagonist supersets — press and row, biceps and triceps in turn: while one muscle works, the other rests. More on what a superset is.
Fewer warm-up sets on the second and third exercises: you're already warm.
Machines at the end — moving a pin is faster than loading plates.
Fewer exercises, same volume — four sets of one exercise instead of two sets each of two.

When a long workout is fine

Strength programs with heavy sets of 1–5 reps take longer: 3–5 minutes of rest plus a long warm-up up to the working weight. Ninety minutes for a heavy squat and bench is normal. Same for leg day: squats, deadlifts and leg presses just take time.

The warning sign isn't length but that by the end you can't work with a normal weight, and the last exercises in your log haven't moved in months. Then shorten or split the workout instead of grinding through.

What to track in the log

Workout time on its own says nothing. What matters is how many hard sets you did and whether the weight or reps in them are rising. If you do in 50 minutes what used to take 80, that's progress in conditioning and rest discipline.

I time the workout, count sets and tonnage, and show for every exercise whether the estimated max went up. A short workout where everything grows beats a long one where nothing moves.

A worked example

Take the "Push" day from push/pull/legs: six exercises, 19 working sets. The bench and overhead press — 7 sets at three minutes each with rest, about 21 minutes. Another 12 sets of isolation and dumbbell pressing at two minutes each — 24 minutes. Add a 10-minute warm-up and about five minutes moving between stations. Roughly an hour.

Done without a timer, with your phone and some chatting, the same workout easily stretches to ninety minutes — for the same work. If you need to finish in 45 minutes, it's easier to cut one exercise and add a set to the others than to shorten your bench rest.

Common questions

Is a workout over an hour harmful? No. There's no 45-minute "window" after which muscles stop growing. The only question is whether you still have the energy for quality sets at the end.

What if I only have 30 minutes? Do 10–12 working sets, mostly compounds, plus supersets. Three short workouts a week beat one long one that never happens.

Should cardio go in the same workout? If the goal is strength and muscle, do cardio after lifting or on another day so you're not tired before the heavy sets. A five-minute warm-up on the treadmill doesn't count — it only helps. More in the warm-up guide.

Start the rest timer and log your sets — I'll show how long the workout took and how much you did.

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