It is important to remember that the human body is designed to work more effectively in certain positions. This is when the body assumes neutral and relaxed postures. An appropriately adjusted workstation will help to achieve such postures. A good working posture increases efficiency, reduces fatigue and the risk of injury. It is also important to note, that a “good working posture” is not a single, rigidly defined position.
The user of screen based equipment (computers) must be able to adopt a comfortable work posture. Discomfort and pain are most likely to be caused by constrained postures, which result in static muscle loads which lead to early fatigue.
The following principles are useful for assuming appropriate working postures:
- Feet are supported on the floor, or a footrest (so that knees are at 90° angle).
- Thighs are supported by the chair seat with no pressure caused by the front edge of the seat under the thighs.
- Upper body is upright with the lower back firmly supported by the backrest so the lumbar curve is maintained.
- Shoulders are in a relaxed position and are not hunched
- Elbows and upper arms are close to the body ·Upper arms perpendicular to floor (i.e. shoulders in neutral)
- Elbows at 90° so that forearms parallel to the ground
- The wrists are in a neutral position (straight) when utilizing the keyboard and mouse
- Neck remains in a neutral position when viewing the monitor, i.e. not looking upwards or downwards and not with chin protruding forwards.
The most common cause of lower back pain at work is due to poor posture (e.g. slouching over a desk). The easiest way of relieving pain is to sit up straight and utilize lumbar support. This can be achieved with the use of an ergonomic chair, a lumbar roll and by strengthening the core muscles while you work. Using an exercise ball as a chair, when working at a desk, is “active sitting”. Human beings tend to sit with poor posture, even in ergonomic desk chairs, as we tend to slump. Sitting on an exercise ball, your body is constantly making small adjustments – with the postural muscles, abdominals, gluteals and leg muscles – in order to stay balanced. In fact it’s pretty hard to slouch on an exercise ball because you will probably fall off. However, it is recommended that if an exercise ball is utilized, this should not be as an alternative to an appropriate ergonomic chair and should be used for no more than 50 percent** of the sitting required. This is due to fatigue from the level of muscle activity required in sustaining an upright posture, over prolonged periods, on the ball.
**When you start using the ball at work do it for short periods, for example 20 minutes three times a day and gradually build up the length of time.