Lying Leg Curl
The lying leg curl is a machine exercise in which you lie face down and curl a padded lever from straight legs up toward your glutes. It isolates the hamstrings, the muscles on the back of your thigh, in their job of bending the knee. That makes it the natural partner to hip hinges like the Romanian deadlift.
How to do the lying leg curl
Adjust the machine so your knees sit just past the edge of the bench, in line with the machine's pivot.
Lie face down and set the lever pad on the back of your lower legs, just above your heels.
Hold the handles, press your hips into the bench and keep your legs straight to start.
Bend your knees and bring your heels toward your glutes as far as you can, with your hips pressed into the pad.
Hold the top briefly, then lower the pad under control until your knees are almost straight again.
Setting up the lying leg curl machine
Lie down on the bench before you pick a weight and check two things. First, your knees: they should sit just past the end of the pad, so the joint lines up with the machine’s pivot, often marked with a dot. Second, the lever pad: it should rest on the back of your lower legs just above your heels, low enough to stay put through the whole curl. Many lying curl benches are angled at the hips; that slight bend is intended, so let your hips settle into it.
Bracing and breathing
Hold the handles and pull yourself down into the bench, so your hips stay pressed into the pad. Breathe out as you curl and in as you lower. Keep your upper body relaxed; your chest stays on the bench and your head in line with your spine.
Range of motion and tempo
Start each rep from almost straight legs and curl your heels toward your glutes as far as the machine and your hamstrings allow. Hold the top for a moment, then lower the pad at least as slowly as you raised it. Turn around just before the stack touches, so the hamstrings stay loaded between reps.
Hips down, every rep
The most common way to cheat this exercise is to lift the hips. It makes the curl feel easier, because your hips and lower back start to help, and it makes one session impossible to compare with the next. If you cannot finish a rep with your hips on the pad, the weight is too heavy.
Choosing the weight
Light loads build muscle about as well as heavy ones when sets are taken to or very near failure, so there is no need to load this exercise to the point where form breaks. Taking every set to failure has shown at most a trivial extra benefit for growth.
Muscles worked by the lying leg curl
- Primary
- Hamstrings
- Secondary
- Calves
The hamstrings do the work: the muscles on the back of the thigh that bend the knee; all of them except the short head of the biceps femoris also extend the hip. Your calf muscle crosses the knee as well and helps with the curl. In a study that compared ten exercises, the leg curl leaned more on the inner hamstrings, while hip extension exercises favored the outer long head. That is why a leg curl and a hip hinge complement each other instead of doing the same job.
Common lying leg curl mistakes
Lifting the hips off the pad
When the hips rise, your hips and lower back start to help and your reps stop being comparable. Press your hips into the bench and pull on the handles to keep them down.
Knees out of line with the pivot
If your knees sit too far up the bench or hang off it, the pad slides and the load feels uneven. Move until your knee joint lines up with the machine's axis.
Cutting the curl short
Stopping halfway leaves out the end of the curl, where the hamstrings shorten most. Curl as far as you can and hold the top for a moment.
Swinging the weight up
A jerk from the bottom lets momentum carry the pad. Start each rep smoothly from straight legs and keep the speed even.
Letting the stack drop
Dropping the lever skips the lowering half, which trains the hamstrings too. Lower under control and turn around just before the plates touch.
Leg curl tips from the Muscla training logic
- Do leg curls after your squats and hip hinges. Muscla puts isolation exercises at the end of a session and plans no warm-up sets for them.
- End each set with about one rep in reserve, two if you are new to training. That is Muscla's target for isolation exercises.
- Rest 75 seconds between sets when you train for muscle, 90 seconds for strength and 60 seconds for other goals.
- Earn the next plate with reps. When every set reaches the top of your range, add one step, at least the smallest jump of the stack (usually 5 kg or 10 lb), and start at the bottom again; otherwise add one rep.
- After three sessions without progress, Muscla lowers the weight by 10 percent and builds back up. After every third 4-week block comes a deload week at 90 percent of the weight with one set fewer.
Lying leg curl sets and reps by goal
| Goal | Reps | Rest |
|---|---|---|
| Strength | 8–12 | 90 s |
| Muscle | 10–15 → 12–20 | 75 s |
| Lose fat | 10–15 | 60 s |
| Fit | 10–15 | 60 s |
| Comeback | 10–15 | 60 s |
An arrow marks the range for the next 4-week block.
The lying leg curl counts as isolation in the Muscla training logic: higher rep ranges and shorter rests than squats and deadlifts. For muscle, start at 10–15 reps and move to 12–20 in the next 4-week block. Each set counts fully toward your weekly hamstring sets.
Lying leg curl alternatives
Lying leg curl questions
Lying or seated leg curl: which is better?
Both train the hamstrings, but seated leg curls built more. In a 12-week study, the seated curl grew the hamstrings by about 14 percent, the lying curl by about 9 percent, because sitting keeps the hamstrings longer at the hip. The lying curl is still a good choice when no seated machine is free.
Do I need leg curls if I do Romanian deadlifts?
They add something. The Romanian deadlift trains the hamstrings through the hip, the leg curl through the knee, and the two lean on different parts of the muscle. Muscla adds hamstring curls next to its hip hinges for that reason.
How heavy should lying leg curls be?
Heavy enough that the last reps are hard, light enough to keep your hips down and curl the full range. For a man new to training, Muscla's first suggestion is about 0.25 times body weight, rounded down to the stack.
Should my feet be pointed or flexed?
Pull your toes toward your shins and keep them there for the whole set. Whatever you choose, keep it the same every session, so your numbers stay comparable.
Why do my calves cramp during leg curls?
Your calf muscle crosses the knee and helps bend it, so it works in every rep and can tire or cramp. If cramps keep coming back, have it checked.
How many sets of leg curls per week?
Count them with your other hamstring work. When you train for muscle, Muscla plans 8–12 hard sets a week for the hamstrings if you are new, 10–16 if you train regularly and 12–20 if you are experienced.
Train it with Muscla
Muscla plans your sets, reps and rest, and sets the next weight after every session.
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Sources
- Maeo S, Huang M, Wu Y, et al. Greater hamstrings muscle hypertrophy but similar damage protection after training at long versus short muscle lengths. Med Sci Sports Exerc. 2021;53(4):825-837. PubMed
- Bourne MN, Williams MD, Opar DA, et al. Impact of exercise selection on hamstring muscle activation. Br J Sports Med. 2017;51(13):1021-1028. PubMed
- Schoenfeld BJ, Grgic J, Ogborn D, Krieger JW. Strength and hypertrophy adaptations between low- vs. high-load resistance training: a systematic review and meta-analysis. J Strength Cond Res. 2017;31(12):3508-3523. PubMed
- Refalo MC, Helms ER, Trexler ET, et al. Influence of resistance training proximity-to-failure on skeletal muscle hypertrophy: a systematic review with meta-analysis. Sports Med. 2023;53(3):649-665. PubMed