Once again placing the BOSU ball upside down increases the instability and makes the exercises harder. Any exercise on an upright BOSU ball can be performed on the upside down BOSU Ball. Squat down to lower your center of gravity, which increases the difficulty of maintaining your balance. Then rotate and shift your upper body to change your center of gravity and cause the core muscles to respond and maintain balance. The exercise can also be performed while reaching for the corner of an imaginary box. This intern also enjoyed performing the Macarena on the BOSU ball.