Ball chairs, whats the hype about?
Are you thinking about trading your desk chair in for an exercise ball? There are pros and cons to doing so. The appeal lies in feeling like you are getting a work out in while just sitting at your desk and working all day. The instability and movement of the ball helps to keep your core constantly active and build muscles that important in keeping you healthy and pain free. However, if used incorrectly or before you have adequate strength to stabilize yourself, sitting on a ball can do more harm than good.
The biggest draw back to sitting on a ball is its lack of ergonomic support and individual adjustment. Most normal desk chairs have arm rests and lumbar support built in to put you in a more optimal position and provide support. When sitting on the ball your own strength has to provide all this support which can be very taxing. Desk chairs also have lots of individual adjustment to change everything from seat height and arm rest height to seat angle and lumbar support. The exercise balls come in different diameters and the size of the ball should be determined based on your height, generally 55 cm and 65 cm balls are the most common sizes used but larger and smaller balls are available for those who are shorter and taller. When selecting a ball size you want to make sure that when you sit on the ball your hips and knees both rest at a 90 degree angle, that your feet are on the floor or a foot rest and that you monitor is at eye level and your elbows rest at a 90 degree angle on the keyboard (this holds true to normal desk chairs as well) If these positions are off then you need to change the height of your ball or your desk.
Generally, switching out your chair for a ball can be a great way to get some extra strengthening in. Like most new things it is good to start out in moderation and switch between the ball and a chair in 30-60 minutes increments and build up to being able to sit for a full day without getting fatigued. If you have back pain at all, it would be advised to consult your physical therapist before switching to make sure you have adequate stability in order to prevent further injury.