Seated Leg Curl: how to do it right
In short: The seated leg curl isolates the hamstrings by loading them heavily in the lengthened position, hip flexed and knee straight.
How to do it, step by step
- 1Adjust the backrest so your knee lines up with the machine's axis of rotation, with the pad snug above your ankles.
- 2Lock your thighs under the lap pad so your pelvis does not move.
- 3Bend your knees, pulling your heels toward your butt, until the hamstrings are fully contracted.
- 4Come back slowly over 2 to 3 seconds, letting your legs straighten, with no jerk or bounce.
- 5Go for almost full extension to maximize the stretch, then flow into the next rep without a sudden stop.
The mistake to avoid
Don't lift your hips off the seat to cheat.
Other common mistakes
- Letting the weight pull you and bounce at the bottom: actively brake for 2 to 3 seconds to keep the tension in the stretch.
- Lifting your butt or arching to cheat: lock the pelvis under the pad and let only the knee work.
- Cutting the range out of fear of the stretch: go for full extension, it is the core benefit of this movement.
- Going too heavy and losing eccentric control: lower the weight to master the whole lengthening phase.
Muscles worked
- Main:
- Hamstrings
Hamstrings are the main target: biceps femoris (long and short head), semitendinosus and semimembranosus. On this machine, with the hip flexed, the two-joint muscles (semitendinosus, semimembranosus, long head of the biceps) are pre-stretched, so they are recruited more. The calves (gastrocnemius) contribute discreetly as knee flexors.
What to replace it with
Same muscle, same part of the movement: these exercises do the same job.
Frequently asked questions
How do I do this exercise?
Settle in with your back pressed to the backrest, the lap pad locking your thighs, the ankle pad above your heels. Bend your knees, pulling your heels under the seat until full contraction, then let your legs straighten slowly with no bounce. Only the knee moves, the pelvis stays fixed.
How far should I go?
Pull your heels all the way under the seat for full contraction, then let your legs straighten almost fully on the return. The peak load is in the lengthened position, legs almost straight, so that is where range matters most. Never cut the end of the range out of fear of the stretch, it is the whole benefit of the exercise.
I don't feel anything, is that normal?
Slow down the phase where your legs straighten and add a one-second pause at maximum lengthened position, tension held without letting go. You will feel the hamstrings working high up toward the knee, which the lying leg curl does not give. If you mostly feel your calves, focus on the heel pulling, not the toe.
How fast should I do the movement?
Brake the extension, the phase where your legs straighten, over 2 to 3 seconds. The flexion can be firm but controlled. It is the braking in the lengthening that does the real work, not the speed of the return.
How should I breathe?
Breathe in before bending, breathe out as you bring your heels back (concentric phase), breathe in on the braked return. Keep your belly braced and your lower back pressed into the backrest to stabilize the pelvis.