How to do the Leg Curl (Machine)

Muscles worked: hamstrings (back of the thigh), with the calves assisting.

The leg curl isolates the hamstrings. Strong hamstrings balance the front of the thigh and help protect the knee.

How to do the Leg Curl (Machine)

1. Sit so the pad rests just above your heels and the thigh pad holds your legs down.
2. Curl your heels towards your seat.
3. Return slowly, with no jerking.

Watch a short demo11 s video by Renaissance Periodization. Opens YouTube.

Form cues

• Set the pad just above the heel, not on the calf muscle.
• Squeeze at the back for a beat.
• Lower for 2 to 3 seconds.

Common mistakes and fixes

Hips lifting off the seat

Use less weight and keep your hips pressed down.

Jerking the weight

Smooth reps only. If you need momentum, the weight is too heavy.

Short range of motion

Go all the way back and let the stack come all the way forward under control.

Avoid: Lifting your hips off the seat.

How heavy should you start?

Choose a light weight for 10 to 12 reps. Hamstrings cramp easily at first, so progress slowly.

The method works for any lift: see how much weight a beginner should lift and sets, reps and rest.

Alternatives

If the machine is busy or you cannot use it, try: Romanian deadlift with dumbbells or Swiss ball hamstring curl.

Questions about the leg curl (machine)

Seated or lying leg curl?

Both work the hamstrings. Some people find the seated version gentler on the lower back. Use whichever your gym has.

Why do my hamstrings cramp?

New muscle, low hydration or too much weight. Reduce the load, sip water through the session, and stretch gently after.

Exercises that go well with it

• 
  Leg PressLegs · 10 to 12 reps
• 
  Glute BridgeGlutes · 12 to 15 reps
• 
  Cable KickbackGlutes · 12 each leg reps

Stop a set if you feel sharp pain, pinching or numbness, and ask a doctor or physiotherapist about it. Normal muscle burn is fine. Joint pain is not.