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That's the Way the Ball Bounces!

Did you know the average American sits 14 hours a day?!? Unless you "squirm" in your chair (see "Squirm for Health") or have a job that requires you to sit and stand every 30 minutes, you sit too long. There's a good chance you've seen advertisements for new types of seating and alternative chairs that are intended to promote "active sitting" and better postures. One of these, the kneeling chair, has been around for a couple of decades. More recently, companies have been promoting exercise balls, moving discs and bouncing stools as alternative active seating. Should you invest in one of these? Are they better for you from an ergonomic standpoint?

An "ergonomic" chair is the chair that supports the users' natural postural alignment. Users of alternative seating need to be particularly aware of their pelvic angle and spinal alignment. Alternative seating is a great improvement over traditional nonadjustable seating that increases lumbar pressure up to 30%. When a chair seat is flat, it reduces the natural curve in the lower spine, compressing the vertebrae and causing lower back strain. This posture is called "kyphosis" and is illustrated below. If a seat (or ball or stool) permits the pelvis to rest in its natural position (a slight downward tilt), the spine stays curved, reducing strain in the back, neck and shoulders. This "open hip angle" is called "lordosis" and is the natural curve of the spine when you are standing (illustrated below). This angle is not possible when an individual sits in the slump position. Slumping is not a natural postural alignment, however, researchers have found it is a habituated posture when our attention is distracted by functional tasks. In fact, the slump is discouraged by sitting on the ball because this harmful posture increases the ball's instability.

The most positive aspect of alternative sitting is the continual posture correction that reduces the static loading of the spine. Traditional nonadjustable chairs do not encourage movement. The end result is that our body becomes weaker, less able to support itself, and less able to cope with the pressures that we put on it. A healthy body is an active body. However, some people do not have strong enough abdominal and back muscles to support them in the "active" positions for long periods of time. Some people need firm support in their low back, while others need a narrow support on their mid back.

Most (not all!) alternative seating options encourage movement while sitting which improves circulation to the intervertebral discs and lower extremities, improves conditioning of low back muscles and improves stabilization of the spine. If users sit too long on alternative seating and have weak back muscles, they will quickly fatigue and be unable to sit in a natural position. If an individual sits too long in a kneeling chair that does not move, there will be increased pressure on the knees and spine. The original kneeling chair was a rocking chair designed for short term sitting. The Fitness ball was designed to be used during physical therapy sessions as part of a spinal stabilization exercise program. Both can be used in an office setting if they are the correct size (or can be adjusted to the correct height) for you and your workstation. NO seating will prevent back pain if the environment is not adjusted to fit the user.

If you are considering alternative seating, find the model that fits you best. This will take some research and sit time. The only way you will be able to decide if it is appropriate for you is to sit on in while you are being distracted by functional tasks. Alternative seating is indeed an excellent supplementation to an adjustable chair that is adjusted to fit the user. Give it a try and see what you think!

Please refer to our Seating Products web page and select Alternative Seating on the menu for our recommendations on kneeling chairs and fitness balls.

Any back store will have some options, as well.

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