Exercise library / Legs
Leg curl (machine)
Legs · Machine
The hamstrings do two things: they bend the knee and extend the hip. The Romanian deadlift trains the second. The leg curl is the only common exercise that trains the first.
That is why a leg programme with only squats and deadlifts is incomplete, however heavy you go.
Sets, reps and RIR
Machines and cables hold the path for you, so you can work closer to failure than with free weights.
RIR means reps in reserve: how many you could still have done when you racked it. RIR 2 is two short of failure.
How to do it
- Set the pad so it sits just above your heel, not up on your calf.
- Line the machine's pivot up with your knee joint.
- Lie or sit tight against the pad, hips in contact throughout.
- Curl your heel towards your glutes as far as the machine allows.
- Squeeze for a moment at the top.
- Lower under control over two to three seconds. The way down is where the hamstring tolerates most.
Common mistakes
- Hips lifting off the pad
- You are using hip flexion to help the knee. Drop the weight until the hips stay down.
- Dropping the weight
- Hamstrings are particularly prone to strain injuries, and eccentric control is exactly what protects against them. Letting the weight fall throws away half the benefit.
- Pad too high on the calf
- A pad in the middle of the calf shortens the lever and makes the machine feel lighter than it is. Put it at the heel.
- Cutting the range short
- Curl all the way in. Stopping halfway skips the part where the hamstring is shortest.
How it differs from the neighbouring variants
The Romanian deadlift trains the hamstrings stretched across the hip, and loads far heavier. The two are not alternatives, they are two halves.
The single-leg curl exposes side-to-side differences that are common and often large. The Nordic hamstring curl is the same knee flexion with body weight, almost entirely eccentric, and has more research behind it for injury prevention than any other hamstring exercise. The seated curl gives more stretch than the lying version, because the hip is flexed.
What it suits
Leg curls fit late in a leg session, at ten to fifteen reps with a controlled descent. Two or three sets a week is enough. If you play football or sprint, this and the Nordic curl are the two exercises that matter most for the back of the thigh.
Muscles worked
Primary: Hamstrings.
Secondary: Calves.
Estimate your one-rep max
Epley's formula, from a set you have actually done. It is an estimate, and it drifts above eight reps, so keep the input between one and twelve.
Enter a set to see the estimate.
What it is called elsewhere
- Norsk Beincurl (maskin)
- Svenska Bencurl (maskin)
- Dansk Leg curl (maskine)
- Deutsch Beinbeugen (Maschine)
- Español Curl femoral (máquina)
- Italiano Leg curl (macchina)
- Português Mesa flexora
- Русский Сгибания ног в тренажёре
- Français Leg curl (machine)
Related legs exercises
athlate logs this exercise, keeps the numbers, and tells you what you lifted last time.