How long should a workout be? It depends on your sets

There's no magic number, but most effective strength sessions take 45 to 75 minutes, warm-ups included. What decides the length is how many hard sets you do and how long you rest between them, not the clock itself.

Do the math on your session

A hard set takes about a minute, and rest is usually two to three minutes on the big lifts and one to two on the rest. So each set costs roughly two to four minutes. Fifteen sets with warm-ups lands around an hour.

Is a longer workout better?

Only up to a point. After roughly 6 to 8 hard sets for one muscle in a session, each extra set does less, and fatigue makes later exercises worse. If your sessions run past 90 minutes, you'll usually do better spreading the work over more days. See how often to train each muscle.

What makes workouts run long

• Resting longer than you planned, usually while on your phone. A rest timer that starts itself helps.
• Too many exercises. Four to six is plenty.
• Waiting for equipment. Have a swap ready for busy machines.

How to train well in 30 minutes

1. Do two or three compound lifts, not six exercises.
2. Pair exercises for different muscles as supersets.
3. Keep warm-ups short: one or two lighter sets of the first lift.
4. Stop each set one or two reps short of failure so you can keep the rest short.

More in our 30-minute strength workout.

In Liftsmith you set how long you have today with a slider, and the plan fits the time, warm-ups and rest included: a short day drops exercises from the end, a long day adds them. Link two exercises as a superset and the time saved is counted in.