Fatigue Management

The main ingredients in the prevention of fatigue are:
a. imposing sensible work demands and schedules;
b. maintaining an appropriate diet;
c. fostering morale, and whenever possible;
d. avoiding or reducing sleep debt.
The latter is best achieved by establishing regular schedules for work, rest
and sleep, using napping when sleep schedules are disrupted by operations,
and ensuring that you and your soldiers know their tolerance to sleep loss and
their minimum sleep requirements by experiencing sleep loss in training.
Sometimes when situations were desperate for manning,
platoons would adopt a very low profile and seek very thick
scrub or thorny bamboo to back up against and man a
half-moon perimeter with only two guns manned to allow
the soldiers to get some rest. There is not much advantage
in stopping for a night and only having three hours sleep
after a hard day's patrol. Tired Diggers will be the end
result and ones that are not alert usually are the first to
become casualties - or their immediate neighbours.
Gary McKay
Delta Four: Australian Riflemen
in Vietnam, 1996
Sustained Work Limits and Minimum Sleep Schedules
Sleep loss may not seriously degrade gross motor
Minimum Sleep:
physical performance (eg, trench digging, marching) Rules of Thumb
for 18-40 hours. Beyond 40 hours, however, even
physical performance will rapidly degrade. Mental
abilities and fine motor coordination (as used in Mainly Physical work:
operating equipment and technical maintenance
3 hours of uninterrupted
sleep per 24 hour period
work) are more sensitive to sleep loss and usually forupto9-14days
deteriorating to unacceptable levels after only 18
hours of sustained work. After 36 hours of Mainly Mental work:
continuous wakefulness, most tasks involving 4 hours of uninterrupted
sleep per 24 hour period
perceptual, mental or fine motor skills degrade
forupto4-6days
sharply, for example, sustained attention to brief,
irregular signals and complex planning can erode by Note: There will be individual
differences among personnel -
up to 50 per cent from baseline performance levels. some will require more sleep in
order to remain effective
After 72 hours of sustained operations, almost all
soldiers will exhibit significant and persistent symptoms of fatigue that
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