Seated Single Leg Knee Flexion

Muscles worked

Setup

1. Sit on the edge of a flat bench with your back straight and core engaged.
2. Extend your target leg straight out in front of you with your heel resting lightly on the floor.
3. Place your hands on the sides of the bench for stability and keep your non-working foot flat on the ground for balance.

How to do it

1. Exhale as you pull your heel back toward the bench by flexing your knee, maintaining light contact with the floor to create friction resistance.
2. Squeeze your hamstring hard at the point of maximum flexion, pulling the heel as far under the bench as possible.
3. Inhale as you slowly extend your leg back to the starting position using a controlled 3-second tempo.

Form checklist

• Keep your torso stationary; avoid leaning backward to create momentum.
• Ensure the movement is driven entirely by the hamstring, not by pushing off the non-working leg.
• Keep your hips level and firmly planted on the bench throughout the set.
• Maintain a flexed foot (toes pointed up) to emphasize hamstring engagement over the calves.

Pro tips

• Press your heel firmly into the floor as you pull back to increase the resistance through friction.
• Visualize your heel moving in a smooth arc toward your glute to maximize the shortening of the hamstring fibers.

Make it harder

• Perform the movement with your foot hovering one inch off the floor to remove friction and increase constant tension.
• Wrap a resistance band around your ankle and anchor it to a point in front of you to provide progressive resistance.

Frequently asked

What muscles does the seated single leg knee flexion work?

The seated single leg knee flexion primarily targets the hamstrings, and also works the abs and glutes as secondary muscles.

What equipment do you need for the seated single leg knee flexion?

The seated single leg knee flexion requires no equipment — just your body weight.

Is the seated single leg knee flexion good for beginners?

Yes. The seated single leg knee flexion is a beginner-friendly movement and a strong foundation to build on.

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