Abs · Other

Jack Knife (Suspension)

A compound movement that trains your abs. Your quadriceps and shoulders help out.

EquipmentOther
TypeCompound
Push or pullPull
LevelIntermediate

Muscles you'll work

Jack Knife (Suspension) muscles worked, front viewJack Knife (Suspension) muscles worked, back view
AbsPrimaryQuadriceps · ShouldersSecondary

How to do it

  1. Set up a suspension trainer with the foot cradles hanging approximately mid-calf height.
  2. Lie on your stomach on the floor, facing away from the anchor point. Place both feet into the foot cradles, ensuring they are secure.
  3. Push up into a plank position, supporting your body on your forearms or hands, with your body forming a straight line from head to heels. Engage your core to prevent your hips from sagging or rising too high. This is your starting position.
  4. Keeping your core engaged and your back straight, slowly pull your knees towards your chest while simultaneously lifting your hips slightly towards the ceiling. Your body should form an inverted 'V' shape with your knees tucked in.
  5. Pause briefly at the top of the movement, squeezing your abdominals.
  6. Slowly extend your legs back to the starting plank position, maintaining control throughout the movement and avoiding letting your hips drop.

More ab exercises

Ab RollerDecline Crunch (Weighted)Knee/Hip Raise On Parallel BarsPlate Twist
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