Alex Simotas, MD

Hospital for Special Surgery
Board Certified Physiatrist
Specializing In Spine & Sports Medicine

Home > Wellness & Exercise > Behavioral Strategies > Ergonomic Chairs

Ergonomic Chairs

Sitting has become the scapegoat for all back problems. Let’s be absolutely clear: Sitting itself is not harmful to your spine!

Sitting is the posture of our sedentary lifestyle. Many of us spend eight hours a day in an office and a large percentage of that time is spent sitting. Somehow sitting has been targeted as a great cause of back problems. In and of itself, sitting is not a problem. There are no studies that identify sitting as causing injuries to spinal discs or muscles.

Consider the real consequences of sitting—the absence of activity, idleness: Here is what is really happening:

  • Stiffness of the spine, hips, knees and other joints. Shortening of the muscles and ligaments as they adapt to a bent and flexed or foreshortened positions.
  • Deconditioning of muscles, cardiac and respiratory functions. We have weaker muscles, and less endurance. Our heart muscle and respiratory muscles are deconditioned and weaker. Overall deconditioning is a complex change of physiology on various levels down to the efficiency of oxygen extraction of blood from blood capillaries into our muscles.
  • Sensitivity to activities caused by neurologic training of the pain system, making us less able to adapt to higher levels of physical stress.
  • Psychology and motivational factors reduce our physical confidence to perform various normal and more stressful physical activities. Additionally psychic factors are at play. Sitting is often performed during activities of greater stress and tension whether at work on the phone, in front of a computer screen, or driving long distances in a car.
  • Poor circulation occurs when your muscles stop moving and even worse they are held tense.

 

What can we do? Man evolved to have an active lifestyle, to gather and hunt, not to sit around all day long and complain about his back and neck. Sedentary living is only a late development of the last century. We are having a hard time adapting to it.

Unfortunately there is no easy way to change the factors of the sedentary lifestyle. Consider some of the proposed solutions:

  • Ergonomic chairs: While better -styled chairs may afford more relaxation and comfort, they don’t address the fundamental issue of absence of exercise or activity.
  • Exercise lifestyles: The exercise lifestyle has become a movement that for the most part means having a dedicated period of exercise on a regular basis tagged on to a normal working schedule. There is a definite trend suggesting that more regular and intense exercise is beneficial. (This is certainly what I would endorse). However, there is some evidence that even 1-2 hours of daily exercise does not offset the ills of 8-12 hours of sedentariness that has become a norm.
  • Treadmill desk: This is truly a novel concept that challenges the very basis of an idle lifestyle. The idea is to slowly walk while working at a desk. A study at the Mayo Clinic showed patients lost significant weight and experienced significant improvements in a variety of different health parameters including cardiac function, respiratory function and blood pressure.

 

ERGONOMIC CHAIRS

“Ergonomic” generally means it is well contoured to your body and back, with good seat height, depth, and armrests. These features are more likely to keep your muscles and you relaxed during the long hours that you have to remain in the stationary sitting position, often while under some stress.

There are many types of ergonomic chairs available for use in the office. No one type of office chair is necessarily the best. Of course you should consider your own particular tasks and needs. Here are some things to consider:

  • Seat height: Should be adjustable (usually 16 to 21 inches off the floor). Hip, knee and feet should be at 90 degree angles. Normally this allows your thighs and feet to be horizontal, and your elbows and arms should be around the height of the desk.
  • Seat width and depth: Wide enough to be comfortable (usually17-20 inches). Deep enough to allow the back to reach the back rest while allowing 2 to 4 inches between the back of the knees and the edge of the seat.
  • Lumbar support: A long surface to lean up against in a fairly “neutral” position (not too far forward and not too far backward) that provides a long surface for contact keeps your back muscles as relaxed as possible. The lumbar spine usually has an inward curve, called a lordorsis. The actual amount of curve can vary from person to person, so its better if its adjustable. There is no exact correct position of a support, so just make it comfortable.
  • Backrest: Optimally the chair should have a back long or high enough to reach the shoulder blades.
  • Armrests: Adjustable armrests allow the shoulders to be relaxed.
  • Swivel: The ability to rotate allows one to reach different areas of his or her desk without straining.