Leg Extension
A machine-based quad isolation exercise, commonly used as an accessory to add direct quad volume without the fatigue cost of a compound squat.
Equipment: Gym machines (leg press, leg extension, etc.)
How to do it
- 1Sit in the machine with your back against the pad and the ankle pad resting just above your feet.
- 2Adjust the seat so the machine's pivot point lines up with your knee joint.
- 3Extend your legs to lift the pad up until your legs are straight, squeezing your quads at the top.
- 4Lower the weight back down under control to the starting position.
Common mistakes
- Using momentum to kick the weight up instead of a controlled, muscle-driven extension.
- Setting the weight too heavy and letting the lower back lift off the pad to help move it.
Sets & reps by goal
| Goal | Sets | Reps | Rest |
|---|---|---|---|
| Strength | 2-3 | 8-12 | 60-90 sec |
| Build muscle | 2-3 | 10-15 | 60-90 sec |
| General fitness | 2-3 | 12-15 | 45-60 sec |
Ranges reflect the same goal-based logic used by the workout plan tool. These are practical starting ranges rather than exact requirements; actual set count in a generated plan also depends on how often this muscle group appears elsewhere in your week.
Frequently asked questions
Is the Leg Extension safe for beginners?
Generally, yes. The Leg Extension is tagged as beginner-friendly in GetFitArchitect's exercise database, meaning it doesn't demand much prior strength, mobility, or technique. Start with a version you can control throughout, whether that means a lighter weight, an easier variation, or a shorter hold, progress gradually, and stop if something hurts beyond normal muscle effort.
What muscles does the Leg Extension work?
The primary mover is your quads. As a legs movement, it also involves your glutes and hamstrings.
What can I substitute if I don't have gym machines for the Leg Extension?
There's no close equivalent in the database without gym machines. The Sissy Squat trains the same main muscle group, but it's a different movement, so treat it as a broad alternative rather than a direct replacement.
See the Sissy SquatRelated exercises
Learn more
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