Single-Leg Lying Curl
The single-leg lying curl is a lying leg curl performed one leg at a time: lying face down on the machine, you curl one heel towards your glutes against a padded lever. It isolates the hamstrings, with the calf assisting, and trains each leg independently so neither side can carry the other.
Also called: Single-Leg Lying Leg Curl, Unilateral Prone Leg Curl, One-Leg Machine Leg Curl · Equipment: machine · Pattern: pull
Step by step
- Adjust the machine so the knee pivot lines up with your knee joint and the ankle pad sits just above your heel.
- Lie face down with your hips flat on the bench and your knees just past the edge of the pad, and hold the handles.
- Hook one leg under the ankle pad and rest the other leg straight on the bench.
- Press your hips into the pad and brace your trunk.
- Curl your heel towards your glutes as far as you can while your hips stay down.
- Pause briefly, then straighten your leg under control until your knee is almost straight.
- Complete the reps on one leg, then change legs.
- Hips pressed into the pad
- Heel to your glutes
- Pause at the top of the curl
- Control the leg back out
- Knee in line with the pivot
In VALDA, these cues are one tap away on the exercise while you train.
What it trains
| Muscle | Role | Evidence |
|---|---|---|
| Hamstrings: biceps femoris (short head) | Prime mover | B |
| Hamstrings: semitendinosus | Prime mover | B |
| Hamstrings: biceps femoris (long head) | Prime mover | B |
| Hamstrings: semimembranosus | Prime mover | B |
| Gastrocnemius: medial/lateral head | Secondary | C |
Evidence grades: A = strong research base · B = good · C = limited · D = coaching consensus.
What goes wrong, and the fix
Hips lifting off the pad
Fix: Press your hips into the pad and use a load you can curl with your hips down.
Pelvis twisting towards the working leg
Fix: Keep both hips flat and level on the pad throughout the set.
Cutting the range short
Fix: Straighten the leg to just short of lockout on every rep.
Dropping the weight
Fix: Take about two seconds to straighten the leg on every rep.
Knee out of line with the pivot
Fix: Line your knee up with the machine's pivot before the first rep.
What the research says
Muscle growth · first choiceRehab & prehab · first choiceGeneral fitnessSport performanceEndurance
- Hip position — In a 12-week trial, seated leg curls grew the hamstrings more than lying leg curls (about 14% against 9%), because the bent hip trains the hamstrings at a longer length. The single-leg lying curl uses the lying position.
- Curl versus hinge — In a 10-week trial, knee-flexion training grew the semitendinosus, while hip-extension training grew the biceps femoris long head more. Many lifters pair a curl with a hip-hinge exercise.
- One leg at a time — Research shows the force two limbs produce together is usually less than the sum of each limb working alone, which is one reason single-limb work lets each leg train at its own load.
- Load and effort — Studies show muscle growth is similar across a wide range of loads when sets are taken close to failure, and sets that finish a rep or two short of failure capture most of that benefit.
- Sets and reps — A common approach is 2–4 sets of 8–15 reps per leg.
Log the single-leg lying curl in VALDA, with these cues one tap away while you train and your history for it in one place.
General information about exercise technique, not medical advice. If you have an injury or a health condition, your healthcare provider is the right person to ask.