Lying leg curl machine

Why the lying leg curl works

The lying leg curl trains knee flexion under load. It is one of the few hamstring exercises that isolates the knee flexion function rather than combining it with hip extension.

The target

The hamstrings through knee flexion. Different machines hit slightly different parts of the muscle but all three hamstring muscles (semitendinosus, semimembranosus and biceps femoris) work during leg curls. The exercise complements hip hinge work that emphasises the hip extension function of the hamstrings.

The face down position

Lying face down on the machine fixes your hip position and isolates the knee joint. This focuses the work on the hamstrings rather than allowing other muscles to contribute. The position also keeps your lower back unloaded, which suits training around back issues that limit other hamstring exercises.

Versus seated leg curl

The seated version puts the hamstring in a more stretched position at the start of the rep. Research suggests this stretched starting position produces slightly more hamstring growth. The lying version starts with the hamstring in a more neutral position. Both versions produce hamstring development. Many programmes include both.

When to use it

For direct hamstring work alongside hinge exercises. As accessory work in a hamstring focused programme. For higher rep work to add volume. When lower back issues prevent heavier hinge variations. The machine is widely available so most lifters have access to it.

The setup and technique

Good leg curl technique looks simple but the setup details matter for getting full hamstring loading.

The setup

Lie face down on the machine. Adjust the leg pad so it sits across the back of your ankles, just above the heel. Knees should align with the rotation axis of the machine. Some machines have a pelvic strap or pad to keep you in position. Use it if available. Grip the handles for stability.

The starting position

Legs extended with knees nearly straight (not locked). Hamstrings in a relatively neutral starting position. Toes can be flexed or pointed depending on preference (more on this below). Hips pressed into the bench. Core engaged. Take a breath before starting the rep.

The curl

Curl your heels toward your buttocks by flexing the knees. Squeeze the hamstrings hard at the top. The leg pad should travel as far as it can while keeping hips down. Some machines limit the range. Some allow a fuller curl. Get the most range your machine and body allow.

The return

Lower the weight under control. Avoid letting the weight crash back down. Aim for 2 to 3 seconds on the lowering phase. This is where most of the hamstring growth stimulus comes from. Maintain tension in the hamstrings throughout the lowering. Stop just short of fully straight to keep tension on the muscle.

What to fix

A few common errors limit results on the lying leg curl. Most are easy to address.

Lifting the hips

The most common error. People lift their hips off the bench at the top of the rep, which looks like extra range but actually reduces hamstring loading by recruiting other muscles. Keep your hips firmly pressed into the bench throughout. The range you get with hips down is the range that loads your hamstrings.

Rushing the eccentric

Letting the weight crash back down wastes the lowering phase. The eccentric portion produces strong hamstring growth signal. Slow it to 2 to 3 seconds. Maintain tension throughout. Most people see better results when they slow down on the lowering.

Going too heavy

Using too much weight typically means partial reps, lifting the hips and recruiting other muscles. Strict form with moderate weight produces better hamstring development than poor form with heavy weight. Aim for weights that allow 10 to 15 strict reps.

Not getting the full range

Stopping the curl short or never fully completing the contraction limits the stimulus. Get the leg pad as close to your buttocks as the machine and your body allow. The peak contraction at the top produces useful stimulus. Cheating shorter range gives up some of the benefit.

Where the lying leg curl fits

The exercise serves several roles in a hamstring programme. Most lifters benefit from including some leg curl variations.

For hypertrophy

Three to four sets of 10 to 15 reps with moderate weight. Slow eccentrics for added stimulus. One to two leg curl sessions per week as part of a broader hamstring programme. Pair with hinge variations for complete development. The lying leg curl handles higher volumes well.

For strength

Leg curls are not a primary strength exercise. They suit accessory work in a strength programme. Three sets of 8 to 12 reps adds direct hamstring work alongside heavier compound movements. Strength gains on leg curls support performance in other exercises and are useful for injury prevention.

Foot position variations

Pointing the toes through the curl emphasises the hamstrings. Flexing the feet (pulling toes toward shin) brings in more calf involvement. Toes turned slightly inward or outward shifts emphasis between different hamstring muscles. Most lifters use a neutral or pointed toe position by default.

Drop sets and intensifiers

The machine setup makes drop sets straightforward. After a set to failure, immediately reduce the weight and continue for additional reps. One drop set per session at the end of leg curl work adds significant stimulus without much extra time. Rest pause sets also work well on the machine.

More hamstring exercises

For the seated alternative, our Seated leg curl machine covers the more stretched position version. Standing leg curl machine covers the unilateral version. And Cable leg curls covers the cable variation.