Fatigue Management

Chapter Two
Sleep Loss and Disruption
In spite of the mountain cold all slept like logs on the stony
ground. The rarefied air, though bracing in effect,
probably added to the perpetual fatigue which weighs
down the infantryman between battles. In battle,
weariness slips away, but when the main need is over,
dragging fatigue, the protest of the body against
will-power, begins again.
Mental and nervous reaction
coupled with physical
overstrain take their toll. In
addition, many nights' sleep
are lost altogether while the
remainder are broken by
sentry-go and patrolling …
It fills the infanteer's veins
with mud and covers his brain
with a fog through which he
can see only the words "I must
keep going!"
... The infanteer drops in the
mud or among the rocks, to be
roused an hour or so later by
an N.C.O. saying, "Your turn
as sentry," or an officer saying,
"We've got to go out on a
patrol."
W. B. Russell
The Second Fourteenth Battalion, 1948
The Body Clock. Many bodily functions (eg, temperature, blood pressure,
urine and hormone production, blood composition, heart rate and
metabolism) fluctuate in a systematic way throughout a period that is close to
24 hours per cycle, each peaking and waning at certain times. These cyclical
patterns form a kind of biological clock - the ‘circadian rhythm' (from circa
meaning ‘approximately' and dies meaning ‘day'). Figure 3 demonstrates the
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