Things You'll Need:
- BOSU ball
-
Step 1
Begin by lying on your back on the BOSU ball.
-
Step 2
Keep your knees bent at shoulder-width and place your hands behind your head.
-
Step 3
Pull your abs in tight and crunch up toward the ceiling, then return to the starting position.
-
Step 4
An advanced crunch on the BOSU ball is the same exercise with your legs directly together or raised off the floor at a 90-degree angle.









