Changing Views Of Fatigue - Energy And Fatigue: Chronic Fatigue

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Changing views of fatigue

In today's multitasking, 24/7 society, fatigue is usually thought of as something to be avoided, conquered, or, at the very least, denied. But fatigue did not always have a negative connotation. In medieval writings, for example, fatigue is often portrayed as a positive sign that one has reached one's limit and that it is time to rest.

The notion that fatigue is an unwelcome condition to be studied and, ideally, overcome, first became popular in the mid-19th century, with the advent of industrialization and its demand for a steady source of indefatigable factory workers. By 1900, the study of fatigue was all the rage, with fatigue laboratories cropping up throughout Europe and scholarly papers about the new science of "ergography" filling scientific journals.

Reflecting the zeal of the times, in 1909, a German scientist claimed he had identified the bodily chemical responsible for fatigue, which he dubbed "kenotoxin." To test his theory, he sprayed a classroom of purportedly fatigued (and undoubtedly frightened) German schoolchildren with his "antikenotoxin" antidote. Not surprisingly, the antidote proved ineffective and was abandoned.

Interest in the study of fatigue grew as the military sought to understand how to boost energy and thereby increase the productivity of workers in munitions factories during World War I. Later the focus of military research shifted from physical to mental fatigue as increasing numbers of tasks — from piloting airplanes to operating radar — required sustained mental alertness.

Today, research on fatigue continues, but with the recognition that it is far more multifaceted and complex than earlier generations of scientists might have imagined.

Last updated:	January 23, 2007