For those who spend large amounts of time working with computer workstations, however, three factors have been identified as contributing to ergonomically-related problems. Although any one alone can create problems, the combination of all three produces the most significant risk of injury. While reviewing these factors, keep in mind that they apply to all activities, and not just computer use at work. Also, recognize that you have control over how you work, and that your approach to the work can have a significant impact in preventing future problems. Body postures determine which joints and muscles are used in an activity, as well as the amount of force exerted.
Poor postures place unusual or excessive forces on components of the body.
Examples of poor positions include keeping a computer mouse far from the keyboard or not locating the keyboard and monitor in a straight line from your seat. These kinds of awkward positions create undue stresses at the wrists, shoulders, and neck. This refers to the amount of time a person holds a static position to perform a given task. The longer the same muscle or muscle group is used, the greater the likelihood of both localized and general fatigue. This is why rest breaks or changing tasks is so important to decrease prolonged static postures, and thereby reduce the risk of injury.