Oblique Ball Crunches

Lie on an exercise ball with your lower back curvature pressed against the spherical surface of the ball. Your feet should be bent at the knee and pressed firmly against the floor. The upper torso should be hanging off the top of the ball. Place your hands lightly on either side of your head keeping your elbows out. Do not lock your fingers behind your head.
Lower your torso into a stretch position keeping the neck stationary at all times. This will be your starting position.
With the hips stationary,exhale, flex the waist by contracting the abdominals and curl the shoulders and trunk upward until you feel a contraction on your abdominals.
As you curl upwards turn your left shoulder and body, crunching across your body towards your right knee.
Hold the contraction at the top of the movement for one second and then inhale and return to the starting position.
Repeat for the recommended amount of repetitions before switching sides and repeating the exercise raising your right shoulder and body, and crunching across your body towards your left knee.

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