The star plank is a plank variation that helps build strength in your core, shoulders, arms, and hips. Not to mention it requires a heck of a lot of balance, stability, and coordination to perform.
Begin in a side plank with your right hand planted on the floor beneath your right shoulder. Your right arm should be fully extended and your feet stacked left on top of right.
Once you've established a steady side plank position, begin to raise your left arm and leg into the air. Once here, keep your body in a tight line and hold for a set amount of time or as long as possible. You should look like a star - hence the name.
To return, bring your arm and leg back to the starting position. Repeat on the opposite side.