Safe Sitting

Do your muscles occasionally feel stiff and sore even though all you’ve done throughout the day is work at a desk? The reason could be that you’ve been sitting in the wrong position, perhaps at a computer.

Muscular discomfort and injury are common complaints for office workers. Fortunately, you can prevent or minimize these problems simply by moving around, adjusting your work environment or changing your work habits.

Check Your Body Position

Prolonged work in the same position, especially an unnatural position, can cause discomfort or persistent pain in muscles, tendons and other soft tissues.

Keep your body in a relaxed, natural position. Ideally, your arms should hang relaxed from your shoulders. When you use a keyboard, your arms should be bent at right angles at the elbow. Your hands should be in a straight line with the forearm and your elbows close to the body. Your head should be in line with your body and slightly forward. To achieve the right body position you may have to adjust the height of your chair or work station.

If you use a visual display, the top of the screen should be at, or just slightly below, eye level. This allows your eyes to see the screen at a comfortable angle, without having to tilt your head or move your back muscles.

Your chair should provide good support for your back and the seat is at a height that allows your thighs to be horizontal and your feet flat on the floor. Keep work materials within easy reach. If your job requires extensive telephone use, using a headset can help prevent neck problems.

Give your body some relief from sitting by standing up, stretching or shifting position on your chair throughout the day. Some simple stretching exercises can be done while sitting. When possible, take a break to prevent discomfort and fatigue.

Use the Proper Chair

A well-designed, adjustable chair can favorably affect posture, circulation, the amount of effort required to maintain a position, and the amount of pressure on the spine. Chairs designed for the ergonomic needs of today’s offices are readily available on the market.

If you’re looking for a new chair, keep in mind the following:

  • The seat should adapt to the user, not vice versa.
  • The chair should be stable and fully and easily adjustable from the seated position.
  • The seat pan and backrest should be upholstered in a fabric that absorbs perspiration.
  • The seat pan height should be adjustable and should transfer your weight through the buttocks, not the thighs.
  • The backrest should adjust up/down and backward/forward or flex with body movement for good lumbar support. A forward tilt of the seat pan may relieve body stress by allowing the backrest to follow you.
  • Most office work requires some mobility, so the chair should have wheels or casters (hard casters for soft floors and soft casters for hard floors), with five legs for stability.
  • The front of the seat should be of a “waterfall” design to provide clearance for the flesh of the thigh and prevent reduction of blood circulation.
  • For tasks requiring frequent lateral movements, the seat should swivel.
  • Use a footrest if you can’t adjust the height of your chair or work station enough to relieve pressure under the thigh from the seat. The footrest should be angled and covered with a non-slip surface to provide comfortable support for the feet.

Avoid Repetitive Strain Injury

Repetitive strain injury (RSI) can be any injury associated with repetitive action. Initially, you might not notice soreness when you’re actually doing the work, but you may feel pain in the evening. Early symptoms of RSI are muscle and joint aches and pains, and stiffness in the fingers, hands and neck. If you have these symptoms, don’t dismiss them. These injuries are most easily treated in their initial stages.

Keyboards have been blamed for the vast majority of computer-related injuries. Sore wrists are the most common of all repetitive motion injuries attributed to computer use. To prevent muscle strain, arms should hang straight down from the shoulders and then bend into right angles at the elbows. Don’t force your arms and wrists into uncomfortable and unnatural positions. That could cause inflammation of delicate muscles and consequent pressure against the median nerve, which passes through the carpal tunnel (a narrow passage between the forearm and hand).

Symptoms of carpal tunnel syndrome include: a tingling or numb feeling in the hand and/or fingers; shooting pains in the wrist or forearm; and difficulty clenching the fist or grasping small objects. It’s important to recognize these symptoms at an early stage. If left untreated, carpal tunnel syndrome causes severe discomfort, intense, prolonged pain, and even loss of hand function, often requiring surgery.

Anyone in a job that involves sitting for most of the day should be aware of these types of injuries and take precautions to avoid them.

When using a keyboard, keep your forearm, wrist and hand in a straight line. For more information visit this IBM site on healthy computing.