Legs · Machine
Leg Extension
How to do the leg extension, the muscles it works, and the mistakes to avoid. Pulled straight from the Kovo app's exercise library.
- Equipment
- Machine
- Difficulty
- Beginner
- Logged as
- Weighted reps
- Movement
- Extension
- Mechanic
- Isolation
How to do it
Sit on a leg extension machine with your back against the backrest and the front of your ankles against the padded roller. Grasp the handles on the sides for stability. Extend your legs to lift the weight until your legs are almost straight, then slowly lower the weight back to the starting position.
- 1Sit back in the leg extension machine and extend your knees to lift the pad; you should feel your quadriceps contracting strongly
- 2Pause at the top and squeeze, then lower slowly to feel a stretch
- 3Keep your back against the pad and toes relaxed
Common mistakes
- Don't lock your knees abruptly at the top, maintain control
- Avoid leaning back or arching your lower back
- Don't use momentum or swing the weight up, focus on the muscle contraction
Muscles worked
The leg extension mainly works the quads.
- QuadsPrimary
- GlutesMinor
- HamstringsMinor
- CalvesMinor
Leg Extension strength standards
See how your leg extension ranks, from Bronze to Champion. These are the same standards the Kovo app uses to rank your lifts.
Bronzee1RM90 lb
Silvere1RM150 lb
Golde1RM232.5 lb
Platinume1RM317.5 lb
Diamonde1RM367.5 lb
Champione1RM410 lb
Find your rank
Enter your best set. We estimate your 1RM and match it to a tier.
Kovo tracks this rank automatically as you train, across every lift, and levels you up as you get stronger.
Kovo programs the leg extension for you and tracks it every session.
We build your whole program, drop the right lifts into each workout, and adjust your weights as you get stronger. Free on iOS and Android.
More quads exercises
- How to do the resistance band squat
- How to do the resistance band squat to press
- How to do the resistance band thruster
- How to do the resistance band squat walk
- How to do the barbell squat
- How to do the barbell bulgarian split squat
Last reviewed April 2026.