JACKKNIFE

ADVANCED

The Jackknife requires precise control over the abdominal, gluteal, and thigh muscles, which all benefit from this exercise. While the legs are extended into the air, the spine should be allowed to find as much length as possible.

Lie flat on your back with your arms down by your sides, palms facing down and legs straight up in the air.

Inhale to prepare. Exhale, and squeeze your buttocks, drawing your navel to your spine while lifting your legs up and over your head.

Hold your legs parallel to the floor, keeping the weight on your shoulders.

Inhale, and press your arms into the floor, lifting your hips upward.

Reach your legs straight into the air in a controlled, upward movement.

Exhale, rolling down your spine, and press your palms into the floor to slow movement.

Inhale, and lower your legs down toward the floor while keeping them straight.

Keeping your back flat on the floor, squeeze the inner thighs together.

Repeat sequence three to four times.

ANNOTATION KEY

Bold text indicates active muscles

Gray text indicates stabilizing muscles

* indicates deep muscles

DO IT RIGHT

LOOK FOR

• Extending your limbs as long as possible in opposite directions.

• Squeezing your buttocks and drawing your navel into your spine throughout the exercise.

• Lengthening and relaxing your neck.

AVOID

• Raising your shoulders up to your ears.

• Rolling onto your neck. Your weight should rest on the back of your shoulders.

• Allowing the legs to separate.

BEST FOR

• rectus abdominis

• transversus abdominis

• gluteus maximus

• gluteus medius

• triceps brachii

• adductor longus

QUICK GUIDE

TARGET

• Abdominal muscles

• Inner thighs

• Buttocks

BENEFITS

• Strengthens hip and spine extensors

• Challenges stabilization of the spine against rotation

NOT ADVISABLE IF YOU HAVE

• Neck or shoulder issues

• A herniated disk