Research in cellular biology has shown that the cartilage cells of our inter-vertebral discs receive nourishment from movement rather than from regular blood supply. Normal healthy discs are fed and oxygenated by the constant recycling of the disc fluid that occurs with normal spinal joint movement. This joint motion sucks in fluid filled with oxygen and nutrients and pumps out waste fluid. This process of fluid diffusion is greatly affected by internal disc (intradiscal) pressure. If this movement is insufficient, the spinal discs will gradually lose their elasticity. Cartilage cells begin to die off starting from the centre and gradually working outwards. This process can lead to an eventual prolapse ("slipped disc") with associated severe back pain.
One of the most popular solutions prescribed for increasing joint movement is exercise on a stability ball. These balls are lightweight and affordable, making them an attractive option for the average consumer.
In addition to using exercise balls as fitness equipment, there is also a growing movement toward using balls as chairs. This is particularly evident for office workers. Workers using conventional office chairs and computer furniture often suffer from pain in their lower and/or upper back, due to a lack of movement as well as high-compression loads on their spine. Compression results from performing repetitive, harmful activities such as bending, lifting or twisting. Even prolonged sitting can create abnormally high levels of disc compression which can lead to decreased hydration when more fluid is pushed out of the disc, rather than pulled into the disc. This slowly creates a deflated or dehydrated disc. The medical term for this lack of disc fluid is disc desiccation. This is the MRI finding most commonly used to identify degenerative disc disease.
Stability ball chairs provide a healthy ergonomic option in the workplace. Using a dynamic seat instead of a conventional chair engages “active sitting”. This consistent movement relieves spinal compression and enhances movement allowing for normal fluid diffusion and hydration. The result is improved posture, balance, core strength and productivity. As the body adjusts to the subtle bounce, sway and tilt of the ball, deep core muscles are engaged. These constant small adjustments build the endurance and strength of the postural muscles which facilitate optimal posture.
The bottom line is “active sitting” promotes the health benefits derived from movement, and stability balls provide the best solution.