Apple Macintosh PowerBook 150 - Manual (Page 61)

Health-related information about computer use
Muscle soreness, eye fatigue, and other discomforts and injuries sometimes
associated with using computers can occur from performing any number of
activities. In fact, misuse of the same muscles during multiple activities can
create a problem that might not otherwise exist. For example, if you engage in
nonwork activities that involve repetitive stress on the wrist—such as
bicycling—and also use your computer’s keyboard improperly, you may
increase your likelihood of developing wrist problems. Some individuals are
at greater risk of developing these problems because of their health,
physiology, lifestyle, and general exposure to stress. Work organization and
conditions, such as workstation setup and lighting, also play a part in your
overall health and comfort. Preventing health problems is a multifaceted task
that requires careful attention to the way you use your body every hour of
every day.
The most common health effects associated with using a computer are
musculoskeletal discomfort and eye fatigue. We’ll discuss each area of
concern below.
Musculoskeletal discomfort
As with any activity that involves sitting for long periods of time, using a
computer can make your muscles sore and stiff. To minimize these effects, set
up your work environment carefully, using the guidelines that follow, and take
frequent breaks to rest tired muscles. To make working with your computer
more comfortable, allow enough space in your work area so that you can
change position frequently and maintain a relaxed posture.
Another type of musculoskeletal concern is repetitive stress injuries (RSIs),
also known as cumulative trauma disorders (CTDs). These problems can
occur when a certain muscle or tendon is repeatedly overused and forced into
an unnatural position. The exact causes of RSIs are not totally understood, but
in addition to awkward posture, such factors as the amount of repetition, the
force used in the activity, the individual’s physiology, workplace stress level,
and lifestyle may affect the likelihood of experiencing an RSI.
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