Hamstrings · Isolation movement

Single-Leg Curl

A isolation exercise that targets the hamstrings. Performed with leg curl machine.

Primary muscle

Hamstrings

Secondary muscles

–

Equipment

Machine

Difficulty

Beginner

How to perform the Single-Leg Curl

Set up on the lying or seated leg curl machine but place only one ankle under or against the roller.
Line the working knee up with the machine pivot and brace the hips flat against the pad.
Curl the roller with the single working leg, flexing the knee through its full available range.
Pause at peak knee flexion and feel the isolated hamstring contraction on that side alone.
Lower under control to a straight knee, matching the tempo you will give the other leg.
Complete every rep on one side before switching so each hamstring is trained independently.

Suggested working range: 10–15 reps. Default progression: double progression.

•Letting the stronger leg compensate by shifting the hips toward the working side.
•Rushing the working leg through partial reps instead of a full knee-flexion range.
•Loading heavier than single-leg strength allows and recruiting the lower back to help.
•Skipping the controlled eccentric on the weaker leg, which defeats the imbalance fix.