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Jackknife Sit Up

Muscle Group:

How to do a Jackknife Sit Up

  1. Lie flat on the floor with your legs straight and arms behind your head. Your heels, legs, butt, upper back, head, and arms should be in contact with the floor.
  2. Engage your abs, and simultaneously raise your arms and legs in the air, a few inches off the floor.
  3. Once you’re in that position, inhale and lift your arms and legs toward one another. You should raise your legs to a 45-degree angle and have your arms almost parallel to your legs with your hands touching your shins. Exhale once you touch your shins.
  4. Extend your body back to the starting position and repeat the motion.


Make sure to keep your legs as straight as possible throughout each repetition. This will make the exercise more challenging and effective.

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