Fatigue Management

We have been amusing ourselves by trying to discover the
longest period of absolute quiet. We have been fighting now
continuously for twenty-two days, all day and all night,
and most of us think that absolutely the longest period
during which there was absolutely no sound of gun, or
rifle, fire, throughout the whole time was ten seconds ... We
are all of us certain that we shall no longer be able to sleep
amid perfect quiet, and that the only way to induce sleep
will be to get someone to rattle an empty tin outside one's
bedroom door.
(then) Brigadier John Monash
Letter home from Anzac Cove
20 May 1915
The most debilitating effects of sleep deprivation are psychological rather
than physical. It is a command responsibility to promote an awareness of
sleep loss and fatigue. All personnel should get adequate sleep before
deployment and, during operations, try to sleep at least four to five hours in a
single unbroken period each 24 hours (adequate to keep going indefinitely on a
sustained operation). In critical situations, however, three hours of sleep per
24 hours will suffice for most soldiers to remain effective for up to nine days.
Commanders and personnel who undertake primarily mental work (eg,
technicians) and tasks requiring sustained attention (eg, radio operators)
need more sleep due to both the wearying nature of mental tasks and the
added impact of fatigue on mental activities. Soldiers should use every
opportunity to have short sleeps. Napping is usually beneficial; however,
soldiers need to be aware that waking from naps may be accompanied by a
state of confusion and sluggishness (sleep inertia). Performance evaluation is
necessary to obtain a realistic idea of the severity of the effects of fatigue and
sleep deprivation. These guidelines should be practised during training so
that all personnel learn how to effectively sustain performance.
Before, during and after battle, sleep is the only excuse for
not thinking.
Major General D.C. Spry
Commander 3rd Canadian Infantry
Division, 1944-45
... the fundamentals of war - that soldiers must be trained
before they can fight, fed before they can march, and
relieved before they are worn out.
88
Field Marshal Sir William Slim
Defeat into Victory, 1956