Seated Leg Curl: How to Do It, Muscles Worked & Sets

How to Do the Seated Leg Curl

1

Set the back pad

Adjust the back pad so that when you sit, your knees line up with the pivot point of the machine arm.
2

Set the roller

Set the leg roller across the back of your lower legs, around the lower third — above the ankle, not resting on your Achilles.
3

Lock the thigh pad

Sit with your back flat against the pad and bring the thigh pad down across your lower thighs, just above your knees, so your legs stay in place.
4

Take the handles

Hold the two handles on the thigh-pad frame in front of you and start with your legs almost straight, hamstrings already under tension.
5

Curl your legs down

Bend your knees and pull the roller down and back as far as the machine allows. Pause for a second at the end.
6

Return slowly

Straighten your legs over 2–3 seconds until you feel the stretch again, then repeat.

What Muscles Does the Seated Leg Curl Work?

Primary

Biceps Femoristhe outer hamstring; bends the knee, and its long head also crosses the hip.
Semitendinosusthe inner hamstring; bends the knee and turns the lower leg inward.
Semimembranosusthe inner hamstring; bends the knee and turns the lower leg inward.

Secondary

Gastrocnemiuscrosses the back of the knee and assists the bend.
Gracilis and Sartoriushelp bend the knee.
Popliteusunlocks the knee at the start of the bend.

How Many Sets and Reps Should You Do?

Goal	Sets	Reps	Rest
Muscle Growth	3–4	10–15	90 sec
Strength	3–4	8–10	2 min
Endurance	2–3	15–20	45–60 sec
Beginner	2–3	12–15	90 sec

Common Mistakes That Reduce Results

✕

Knees Off the Pivot

If your knee joint does not line up with the machine's pivot, the pads slide and the movement feels awkward. Move the back pad before you load the machine.

✕

Hips Lifting off the Seat

Pushing your hips up to move the weight takes the work off the hamstrings. Keep them on the seat and lower the load.

✕

Roller in the Wrong Place

A roller sitting up on the calf muscle, or down on the Achilles, is uncomfortable and harder to control. ACE's leg curl instructions put the pad on the lower third of the lower leg and say to avoid contact at or just above the heel.

✕

Dropping the Weight

Letting the stack fall skips the lowering half of the rep. Take 2–3 seconds to straighten your legs.

✕

Half Reps

Stopping short at both ends trains less of the range. Curl as far as the machine allows and straighten until you feel the stretch.

Tips for Better Results

✓

Seated Beats Lying for Growth

In a 12-week study by Maeo and colleagues (2021), seated leg curls grew the hamstrings about 14% against about 9% for lying curls, because sitting holds the hamstrings at a longer length.

✓

Keep Your Back on the Pad

Staying back keeps your hips bent, and that hip position is what gives the seated version its stretch.

✓

Pause at the Bottom

A one-second hold at the end of the curl stops you from swinging the stack into the next rep.

✓

Even Out Your Sides

If one leg takes over, add a set or two of single-leg curls to bring the weaker side up.

Modifications and Progressions

▼ Easier

Lying Leg Curl

The lying machine trains the same knee bend and is a good stand-in when the seated machine is busy.

▼ Easier

Resistance Band Leg Curl

Lying face down and curling one heel toward your glutes against a band needs no machine.

▲ Harder

Single-Leg Seated Leg Curl

Curling with one leg at a time stops a stronger leg from carrying the weaker one.

▲ Harder

Seated Leg Curl with Slow Lowering

Take 3–4 seconds to straighten your legs, which keeps the same weight under tension for longer.

Workout Plans With the Seated Leg Curl

Day 2 — Lower Body 12-Week Lean Bulk Workout Plan: Training and Calorie Guide Beginner Leg Day + Leg Day B Core Workout: Short Ab and Core Plan for Gym or Home

Seated Leg Curl Alternatives

Barbell Romanian Deadlift exercise demonstration

Barbell Romanian Deadlift Hamstrings, Gluteus Maximus

Barbell Deadlift Gluteus Maximus, Hamstrings, Erector Spinae

Frequently Asked Questions

Seated or lying leg curl — which is better?

For muscle growth the seated version has the edge. Maeo and colleagues (2021) trained one leg with each for 12 weeks and measured about 14% hamstring growth from seated curls against about 9% from lying curls.

Where should the roller sit?

Across the back of your lower legs, around the lower third — above the ankle, not up on the calf and not down on your Achilles.

Why do my hamstrings cramp during leg curls?

Cramping usually settles when you lower the weight, slow the reps down and build the number of sets up over a few weeks rather than all at once.

Do leg curls help my squat and deadlift?

They train knee bending, which squats and deadlifts do not. Most programs use them alongside hip hinges such as the Romanian deadlift, not instead of them.

How often should I train hamstrings?

The workout plans on this site train them once or twice a week with 3–4 sets each session.

Sources

American Council on Exercise (ACE). Lying Hamstrings Curl — Exercise Library. https://www.acefitness.org/resources/everyone/exercise-library/153/lying-hamstrings-curl/
Maeo S, Huang M, Wu Y, Sakurai H, Kusagawa Y, Sugiyama T, Kanehisa H, Isaka T. 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. https://pubmed.ncbi.nlm.nih.gov/33009197/

Seated Leg Curl

Exercise Profile