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  7. Dumbbell Sitting Leg Extension

Exercise guide

Dumbbell Sitting Leg Extension

  • Intermediate
  • Isolation
  • Rep-based
  • Lower legs
  • Upper legs

The dumbbell sitting leg extension is a potent isolation exercise that targets the quadriceps, specifically emphasizing the rectus femoris and vastus medialis. Using a dumbbell creates a unique stabilization challenge for the lower legs while allowing for a deep peak contraction.

Reviewed by the Crucible team · Updated June 2026

Watch the Dumbbell Sitting Leg Extension demonstrationGuided video and your full workout live in the Crucible app.

Muscles worked

Primary

  • Quadriceps

Secondary

  • Glutes

Equipment

  • Dumbbell

Setup

  1. Sit on the edge of a flat bench and place a dumbbell vertically on the floor between your feet.
  2. Secure the handle of the dumbbell between your inner arches, squeezing your feet together to lock it in place.
  3. Grip the edges of the bench behind your hips for stability and lean your torso back slightly to create a stable base.
  4. Lift your feet slightly off the floor to create tension in the quadriceps before starting the set.

How to do it

  1. Exhale as you extend your knees, lifting the dumbbell in a smooth arc until your legs are fully straight.
  2. Squeeze your quadriceps forcefully at the top of the movement for a one-second pause.
  3. Inhale as you lower the dumbbell back toward the floor using a controlled 3-second eccentric tempo.
  4. Stop the descent just before the dumbbell touches the floor to maintain constant tension on the muscles.

Form checklist

  • Keep your torso still; do not use your upper body to swing the weight up.
  • Maintain a firm grip on the dumbbell with your feet throughout the entire range of motion.
  • Ensure your knees remain tracking forward and do not cave inward.
  • Keep your core braced to protect your lower back while leaning against the bench.

Pro tips

  • To maximize the contraction of the vastus medialis, focus on achieving a full lockout and slightly rotating your toes outward at the top.
  • Imagine pushing your knees down into the bench as you lift your feet to better isolate the quads and prevent hip flexor dominance.

Make it harder

  • Slow the eccentric phase to 5 seconds to increase metabolic stress and time under tension.
  • Add a 3-second isometric hold at the top of every repetition to maximize muscle fiber recruitment.

Frequently asked

What muscles does the dumbbell sitting leg extension work?
The dumbbell sitting leg extension primarily targets the quadriceps, and also works the glutes as secondary muscles.
What equipment do you need for the dumbbell sitting leg extension?
The dumbbell sitting leg extension uses dumbbell.
Is the dumbbell sitting leg extension good for beginners?
The dumbbell sitting leg extension is rated intermediate. Build a base with simpler variations first, then progress to it with light load and strict form.

Related exercises

  • 3 Point Standing HopsIntermediate · calves, glutes, hamstrings, and quadriceps
  • 4 Cone Single Foot Lateral HopsIntermediate · calves, glutes, hamstrings, and quadriceps
  • 4 Way Single Leg HopAdvanced · calves, glutes, hamstrings, and quadriceps
  • 90 To 90Beginner · abs, glutes, obliques, and quadriceps

Train this with a plan, not guesswork

Crucible builds the dumbbell sitting leg extension into a precise program around your body, equipment, location, and time.

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