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  5. Shoulders
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  7. Seated Elbow To Knee On Chair

Exercise guide

Seated Elbow To Knee On Chair

  • Beginner
  • Compound
  • Rep-based
  • Shoulders
  • Upper arms
  • Upper legs
  • Waist

A beginner-friendly core exercise that targets the obliques and rectus abdominis through seated rotation and hip flexion. It improves rotational mobility and functional core strength while maintaining a stable base on a chair.

Reviewed by the Crucible Fit team · Updated June 2026

Watch the Seated Elbow To Knee On Chair demonstrationVideo and instructions for every movement are in the Crucible Fit app.

Muscles worked

Primary

  • Abs
  • Obliques

Secondary

  • Biceps
  • Deltoids
  • Triceps

Equipment

  • Body weight

Setup

  1. Sit upright on the front edge of a sturdy chair with your feet flat on the floor, hip-width apart.
  2. Place your fingertips lightly behind your ears with your elbows flared out wide to the sides.
  3. Engage your core and maintain a tall, neutral spine with your chest lifted.

How to do it

  1. Exhale as you lift your right knee toward your chest while simultaneously rotating your torso to bring your left elbow toward that knee.
  2. Inhale as you slowly lower your foot and return your torso to the center starting position.
  3. Repeat the movement on the opposite side, bringing your right elbow toward your left knee in an alternating pattern.
  4. Maintain a controlled tempo, focusing on the contraction of the abdominals rather than momentum.

Form checklist

  • Rotate from the waist and mid-back rather than just pulling your elbow forward.
  • Keep your chest open and avoid pulling on your head or neck with your hands.
  • Keep the stationary foot firmly planted on the ground for stability.
  • Maintain an upright posture throughout the movement; do not slouch into the chair.

Pro tips

  • Focus on the mind-muscle connection by imagining your ribcage moving toward your opposite hip bone.
  • Exhale forcefully at the peak of the movement to maximize the contraction of the deep core muscles.

Make it harder

  • Add a 2-second isometric hold at the point where the elbow and knee are closest.
  • Perform the movement while hovering the non-working foot an inch off the ground to increase tension on the lower abs.

Frequently asked

What muscles does the seated elbow to knee on chair work?
The seated elbow to knee on chair primarily targets the abs and obliques, and also works the biceps, deltoids, and triceps as secondary muscles.
What equipment do you need for the seated elbow to knee on chair?
The seated elbow to knee on chair requires no equipment — just your body weight.
Is the seated elbow to knee on chair good for beginners?
Yes. The seated elbow to knee on chair is a beginner-friendly movement and a strong foundation to build on.

Related exercises

  • 45 Degrees Arms PlankIntermediate · abs, deltoids, obliques, and pectorals
  • Ardha Matsyendrasana Yoga PoseIntermediate · abs, glutes, obliques, and trapezius
  • Back Steps PlankIntermediate · abs, lats, and obliques
  • Bear Walk To Rolling RockIntermediate · abs, hamstrings, obliques, and trapezius

Train it with Crucible Fit.

Every movement in this library is in the app with video and instructions, ready for your own sessions on the days between Crucibles. Your first Crucible is on us.

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