Offers a More Stable Base for Balance & Strengthening Can be Use Vigorously. Challenge Postural Reflexes & Work the Abdominal Muscles. Critical Tool in Every Therapy & Fitness Facility. Offers Great Stability by Limiting Movement Forward & Backward The unique peanut shape allows a therapist & patient to share ball, until the patient has the confidence to work alone. Used by physical therapists worldwide, the ball offers stability & treatment options for more physically challenged patients. It s unique shape allows a therapist to work on activities that otherwise may be somewhat risky on a traditional therapy ball. Add.