How to Substitute an Exercise
A substitute trains the same thing with what you have. Here are the three rules, in order, and the case where there is no good answer.
Last updated: 30 September 2026
The three rules, in order
One: it has to train the same primary muscle group. This is the rule that makes it a substitute rather than a different exercise. If the squat rack is taken, a lat pulldown is not a squat alternative. It is a back exercise you did instead of training legs, and the session is now a different session.
Two: you have to be able to do it with what you have. An alternative that needs a cable stack is not an alternative in a hotel room.
Three: the more it shares beyond the primary muscle, the closer it is. A barbell bench press works chest, and along the way shoulders and triceps. A cable chest press works all three. A dumbbell fly works the chest and almost nothing else. All three are chest exercises; only two of them are close substitutes.
Worked
You cannot get to a barbell, and you have dumbbells and a cable stack. Instead of a barbell bench press, which trains chest with shoulders and triceps alongside:
| Alternative | Also trains | How close |
|---|---|---|
| Cable chest press | Shoulders, triceps | Close |
| Incline dumbbell press | Shoulders, triceps | Close |
| Dumbbell fly | — | Loose |
Work it out: the exercise substitute finder applies these three rules to the exercise library and tells you when there is no good answer.
When there is no good answer
Sometimes the honest result is nothing. If you have only your bodyweight and the session called for a heavy squat, there is no replacement that does the same job, and the useful answer is not a worse exercise. It is to move the session, swap the day with a different one in the week, or accept that today is a different kind of training.
A tool that always returns something is a tool that will eventually hand you a lat pulldown for a squat. Prefer the one that says it does not know.
Common questions
Is a machine version a valid substitute for a free weight one?
For the muscle, usually yes. For the skill and the stabilising work, no. If you are training a lift because you want to be good at that lift, the machine is not a substitute; it is a way of keeping the muscle while you cannot practise.
Can I substitute permanently?
If it trains the same thing and you prefer it, yes. Adherence beats optimality by a wide margin, and the best exercise is one you will actually keep doing.
What if I substitute every session?
Then the programme is not the programme any more. Substituting is for the day the rack is busy, not for the whole block.
Sources
NHS strength and flexibility guidance - https://www.nhs.uk/live-well/exercise/strength-and-flexibility-exercises/
American College of Sports Medicine - https://acsm.org/