Definition.com
Posture is nearly connected with the subject of bodily exercise. The usual attitude of a person occupied in reading or writing, tends to obstruct the passage of the blood through the pulmonary and abdominal vessels. Those therefore who are habitually engaged in this manner ought, as much as possible, to stand to their employment. Standing, as it implies muscular exertion, may be regarded as a species of exercise. A valuable treatise might be written on what may be called the diseases of the desk.
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