Intermediate Isolation Core
Jack Knife
Simultaneous arm and leg raise meeting in middle
Looping
HD video demonstration • Hover for controls
Primary Muscles
Abs
Secondary Muscles
Abs
Equipment Required
Bodyweight only
How to Perform
Lie on back. Raise legs and hands simultaneously to meet at the top, forming V-shape. Keep limbs straight. Lower with control.
Form Cues
- Keep limbs straight
- Touch toes at top
- Control descent
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