Exercise guide
Criss Cross Elbow To Knee
- Beginner
- Compound
- Timed hold
- Waist
This dynamic core exercise targets the rectus abdominis and obliques through simultaneous trunk flexion and rotation, improving rotational stability and functional strength.
Reviewed by the Crucible team · Updated June 2026
Muscles worked
Setup
- Lie flat on your back on a mat with your lower back pressed firmly into the floor.
- Place your fingertips lightly behind your head with your elbows flared out wide.
- Lift your legs into a tabletop position with knees bent at 90 degrees and raise your shoulder blades slightly off the mat.
How to do it
- Exhale as you rotate your torso to bring your right elbow toward your left knee while simultaneously extending your right leg straight out at a 45-degree angle.
- Inhale as you transition back through the center, keeping your shoulder blades elevated off the floor.
- Exhale and repeat the movement on the opposite side, bringing your left elbow toward your right knee while extending the left leg.
- Maintain a steady, controlled tempo, alternating sides rhythmically without letting your feet touch the ground.
Form checklist
- Keep your lower back glued to the floor to protect the spine and isolate the abs.
- Rotate from your ribcage and core rather than pulling on your head or neck.
- Keep your elbows wide and out of your peripheral vision to ensure the obliques do the work.
- Fully extend the non-crunching leg to maximize tension in the lower abdominals and quads.
Pro tips
- Focus on bringing your shoulder toward the opposite knee, rather than just the elbow, to achieve a deeper oblique contraction.
- Point your toes and squeeze the quadriceps of the extended leg to maintain total lower body tension.
Make it harder
- Lower the extended leg until it is just a few inches above the floor to increase the lever length and core demand.
- Perform the movement in slow motion, holding the peak contraction for two seconds on each side.
Frequently asked
- What muscles does the criss cross elbow to knee work?
- The criss cross elbow to knee primarily targets the abs and obliques, and also works the glutes as secondary muscles.
- What equipment do you need for the criss cross elbow to knee?
- The criss cross elbow to knee requires no equipment — just your body weight.
- Is the criss cross elbow to knee good for beginners?
- Yes. The criss cross elbow to knee is a beginner-friendly movement and a strong foundation to build on.