Pilates Jackknife: Technique, Muscles Worked and Modifications

How to do the Jackknife

Lie flat on your back on the mat with your legs extended together and your arms resting long by your sides.

1. Lift your legs up toward the ceiling to a ninety degree angle.
2. Peel your spine off the mat to roll your legs backward over your head.
3. Press your arms firmly into the mat using your triceps to support your weight.
4. Squeeze your gluteus maximus to lift your legs straight up toward the ceiling.
5. Reach your toes high so your hips balance directly over your shoulders.
6. Lower your legs slightly back over your head to prepare for the descent.
7. Roll your spine down onto the mat one bone at a time.
8. Return your legs to the starting position with control.

• Breath. Teachers cue the breath differently for this exercise, but a common pattern is to inhale as you roll over, exhale to lift your legs vertical, inhale to hold the shape, and exhale as you roll down.
• Where you feel it. You should feel deep work in your rectus abdominis, spinal extensors, and gluteus maximus, with effort in your triceps and hamstrings. You should not feel sharp pressure or pain in your neck.
• How many. 3 to 5 controlled repetitions

Common mistakes

• Resting on the neck. Keep your weight balanced across your upper back and shoulder blades. Do not let the pressure move up into your cervical spine.
• Using momentum. Rely on your rectus abdominis to lift your hips rather than swinging your legs backward. Move smoothly and deliberately.
• Bending the knees. Keep your legs as straight as possible throughout the entire movement.
• Dropping the hips. Fire your gluteus maximus and spinal extensors to maintain the vertical line when your legs are lifted. Keep reaching your toes up.

Make it easier or harder

Easier

• Practice the standard Roll Over exercise without the vertical leg lift.
• Perform the movement with slightly bent knees to reduce the hamstring stretch.
• Only lift your legs halfway to vertical to build strength in your spinal extensors.

Who should be careful

• If you have osteoporosis or low bone density, or a recent disc injury, ask your clinician whether repeated loaded forward bending of the spine suits you. Many bone health organizations recommend limiting it.
• This exercise puts weight on the shoulders and upper back with the hips above the head. Skip it if you have neck problems, osteoporosis, glaucoma or uncontrolled high blood pressure, or are pregnant, unless a clinician who knows your history has said it is fine.
• This is an advanced exercise. Build the strength and control from the simpler versions first, ideally with a qualified teacher watching.

Related exercises

• Neck Pull Advanced
• Cat Stretch Beginner
• Double Leg Kick Intermediate
• Quadruped Arm and Leg Reach Beginner
• Swan Dive Advanced (prep version beginner)

When to see a doctor or physical therapist

• Sharp or pinching pain in your neck or upper spine.
• Numbness or tingling traveling down your arms.
• A sudden popping sensation in your lower back.
• Dizziness or lightheadedness when inverted.

This page is general education, not a diagnosis or treatment plan. If you have a health condition, are pregnant or are recovering from an injury or surgery, check with your own clinician before trying new exercises.

How we put this page together. Exercise data (type, level, equipment and muscles) was compiled by our editors from the classical mat order in Joseph Pilates’ 1945 book and from commonly taught mat repertoire. Muscle lists are a general anatomy guide; cueing differs between teachers. Text drafted with AI assistance and checked by the Editorial Team. See our editorial policy. Last checked October 2026.