Planks with plates

This is me demonstrating planks using paper plates on NY1-TV

Want to challenge yourself when doing a plank?  Then add plates!  You can use inexpensive, paper plates by placing them on the floor and "circling" clockwise, then counterclockwise (right arm and then left).  Be sure to watch your form!  Arms remain straight, wrists under shoulders, shoulder blades pulled down the back (hint/visualization: imagine you have jeans on that have back pockets--anchor those blades into those pockets!) and keep your stomach engaged the entire time.
Keep your neck aligned with your spine. Also be sure to keep body stable and don't rock--shoulders and hips should remain squared off facing the floor.

If you are doing the right arm you should then feel the work in the right ab/oblique region (under that rib/hip area), same when working on the left.  Go slowly.  If you're new at these then I suggest you start off each side with 5-8 circles clockwise, then repeat 5-8 counterclockwise.  Repeat the sets.  As you get stronger add some more circles to each side.  These are tough, so don't get frustrated!
Good luck :)