The hamstring curl is a machine isolation exercise that trains knee flexion against resistance. Lie or sit on the machine, hook your heels over the pad, and curl your legs toward your glutes — moving only at the knee, with your hips pressed flat.
تمرين ثني الساق هو تمرين انعزالي يستهدف عضلات الفخذ الخلفية، مثالي لزيادة القوة وبناء العضلات.
أسئلة شائعة عن الأداء والسلامة والمعدات والبدائل لهذا التمرين.
The hamstring curl isolates the hamstrings — the biceps femoris, semitendinosus, and semimembranosus on the back of the thigh — through knee flexion. The calves assist slightly because the gastrocnemius also crosses the knee, and the glutes stay contracted to keep the hips down. The machine removes hip movement, so the hamstrings do nearly all the work.
The best options keep knee flexion in the movement: Nordic curls (kneel, anchor your feet, lower your torso under control), swiss-ball or sliding leg curls, and single-leg glute bridges. The Romanian deadlift with dumbbells also trains the hamstrings hard, but through hip extension rather than knee flexion — useful, but not a direct replacement.
Seated wins for hypertrophy. A 2021 study by Maeo found roughly twice the biceps femoris growth from the seated leg curl versus the lying version over 12 weeks at matched volume. The hip-flexed position loads the hamstring in a stretched position, producing more stimulus per set. If your gym only has a lying machine, it still works — the return per set is just slightly lower.
3–4 sets of 8–15 reps, one or two times per week. For hypertrophy, 10–12 reps with a controlled 3-second eccentric works best. For strength, 6–8 reps with heavier load. Aim for 8–14 total weekly sets for the hamstrings, split between the leg curl and a hip-hinge movement like the Romanian deadlift.
This usually happens when your feet are plantarflexed — toes pointed — during the rep. The gastrocnemius crosses the knee and shortens along with the hamstrings, so it ends up sharing the load. Keep your feet in dorsiflexion (toes pulled toward your shins) for the whole set. That small adjustment takes the calf out of the movement and lets the hamstrings do the work.
Yes. The hamstrings have two jobs — bending the knee and extending the hip. Deadlifts and Romanian deadlifts train hip extension hard but barely touch knee flexion. The leg curl is the main exercise that loads that second function. Keeping both a hinge and a curl in your program trains the whole muscle and helps balance knee-joint strength.