Working out with an Exercise (Therapy) Ball helps develop overall muscle tone for your entire body with a low-impact workout. Specific other benefits can include rehabilitating back, hip, and knee injuries; improving flexibility and your cardiovascular system; and providing a powerful workout to improve your core stability, posture, and muscle balance.
The ball is great if you have back problems because it supports your lower back as you exercise and stretch. Core stability is enhanced –the deep muscles in your midsection that work as stabilizers for your entire body. They work together to protect your spine and help with everyday activities.
The ball also supports the lower back and other posterior muscles while exercising, which works to maintain muscle balance. This works both the anterior and posterior muscles.
Seated Leg Lift: