Elevated Jackknife with a Fit Ball

Whew! Wordy title, but I couldn’t think of a snappier way to summarize this exercise. This is a more advanced move for those who have a solid foundation of core work and are looking to turn up the intensity. If you don’t have access to a flat bench, you can also perform this exercise in prone position with shins on the top of the ball and arms in push-up position (wrists in alignment with shoulders). This exercise hits many additional stabilizing muscles, but primarily focuses on the Transversus Abdominus and Rectus Abdominus (think working toward chiseling out that six-pack).

Depending on who you ask, there are actually a few variations of this exercise with slight differences in form. Some people refer to a jackknife movement as one where the hips lift into the air as you draw the knees in. To me, this appears more as a hybrid of the pike. Similar in nature, but with a different spin. Today I’ll share with you, my take on the Jackknife.

Elevated Jackknife with a Fit Ball

Position yourself face down and place forearms on a bench, with shins resting on the top of a Fit Ball. Engage your core and try to maintain a nice, straight line with your body. Just as you would with plank, don’t allow your bottom to lift and don’t allow hips to sag.

Elevated Jackknife OUT

With slow and controlled movement, tuck your pelvis under as you bend your knees and begin to draw the knees in toward the chest.

Elevated JackKnife Middle

Keeping that core strong, try to minimize rounding of the back. Movement should draw from the lower half of the body.

ElevatedJackKnife IN

Everyone’s range of motion is different, so listen to your body. Draw the knees in as far as you can while maintaining form and control. Both the movement in and out should be slow and controlled, relying on the abdominals and not momentum to take you through the reps.


Try for three sets of 15 to start!

Train hard, train safe and have fun!