Medicine (heavy) balls have been used for many decades and have evolved over the years.  We find that the bouncing heavy balls work best for power production and are the most versatile.  These balls go great with the Heavyy Ball DVD.  The most popular sizes are 6 and 8lbs.

Swiss Stability (Big) balls are also a fantstic staple in your home or office. In fact, many people are using them for more ergonomic reasons and replacing their desk or computer chair with an appropriate size ball.  These balls are not meant to be sat on and bounced upon. There are two sizes depending on your height.  Both sizes work well with the Big Ball DVD series.