APEX ZONE

Exercises · Strength

Jackknife Sit-Up

Body only Abdominals

The Jackknife Sit-Up is a strength movement that targets your abdominals. Here's how to do it with clean form.

How to do the Jackknife Sit-Up

  1. Lie flat with arms extended overhead and legs straight.
  2. Simultaneously lift your arms and straight legs, reaching hands toward feet above your midline.
  3. Lower back to the floor with control.
  4. Initiate from the core — don't yank with your arms or swing your legs.

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