A Gym Ball has to offer a fine balance between support and instability. If the ball is too rigid or too soft then the effects on your core stabilising muscle will be compromised. The Reebok Gym Ball performs to these optimal levels even if you are simply using the ball to sit on at a desk or performing dynamic exercises.

Features:

• Ideal for sit ups, back exercises and general fitness
• Diameter: 75cm
• Includes workout DVD