Exercise guide
Crab Knee To Elbow
- Intermediate
- Compound
- Rep-based
- Lower legs
- Shoulders
- Upper legs
- Waist
The Crab Knee to Elbow is a dynamic total-body movement that builds core stability and coordination while engaging the shoulders, triceps, and glutes. It specifically targets the obliques through a rotational crunch while requiring significant isometric strength from the posterior chain.
Reviewed by the Crucible team · Updated June 2026
Muscles worked
Setup
- Sit on the floor with your knees bent and feet flat on the ground, hip-width apart.
- Place your hands behind your hips with fingers pointing toward your heels.
- Press through your hands and heels to lift your hips off the floor into a 'crab' position, keeping your torso roughly parallel to the ground.
How to do it
- Simultaneously lift your right hand and left foot off the floor while maintaining balance on the opposite limbs.
- Exhale and crunch your midsection to bring your right elbow and left knee together over your torso.
- Inhale as you slowly return your hand and foot to the starting position with control.
- Repeat the movement on the opposite side (left elbow to right knee) and continue alternating sides.
Form checklist
- Keep your hips elevated and avoid letting them sag toward the floor during the crunch.
- Maintain a neutral neck position, looking slightly upward rather than tucking the chin.
- Ensure the supporting shoulder stays 'packed' and stable, not shrugging toward the ear.
- Move with a slow, controlled tempo to prioritize balance over speed.
Pro tips
- Focus on driving through the heel of the planted foot to keep the glutes engaged, which provides a more stable base for the rotation.
- Exhale forcefully at the point of contact to deepen the contraction of the transverse abdominis and obliques.
Make it harder
- Perform a 'Crab Toe Touch' by extending the leg fully and reaching for your toes instead of your knee to increase the range of motion.
- Add a 2-second pause at the point of contact to maximize the isometric challenge on your core and stabilizers.
Frequently asked
- What muscles does the crab knee to elbow work?
- The crab knee to elbow primarily targets the abs, deltoids, and obliques, and also works the erector spinae and serratus anterior as secondary muscles.
- What equipment do you need for the crab knee to elbow?
- The crab knee to elbow requires no equipment — just your body weight.
- Is the crab knee to elbow good for beginners?
- The crab knee to elbow is rated intermediate. Build a base with simpler variations first, then progress to it with light load and strict form.
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