GYMNASTIC BALL This studio quality, burst-resistant exercise ball is made of durable PVC material (latex-free for those with latex allergies!) has an anti-slip surface, and was designed for gymnastics practice, posture, strength and agility therapy.  It can be enjoyed and used by anyone, from children to the elderly and the disabled.  The exercises (targeting the abs, back, hips, thighs and buns) are designed to help you gain strength, flexibility, and tone muscle.  It is also used by Physiotherapists in rehab for back injuries, stroke therapy, and balance training