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Human Performance

There are probably others than those mentioned here. Therefore: whatever the

reason – if you do not feel 100% fit for a fight, mentally AND physically, leave

the plane in the hangar that day.

2.6.6.1 Circadian rhythm

The circadian rhythm is an important biological system that helps us maintain

a healthy balance between activity and rest during the day and night.

It is controlled by the internal clock in the brain and is primarily influenced by

light/darkness, but also by sleep, diet and physical activity.

When the circadian

rhythm is disrupted, it

can have negative
consequences for

both our physical and

mental health.

At night, when we sleep / should sleep, our body temperature drops by 1-2
degrees.

We are most alert when our (normal) temperature is highest. That is, afternoon
/ early evening. The temperature is lowest in the early morning hours, which is

also characterized by the fact that we have to wake up first and get going before

we are really fit for a fight.

2.6.6.2 Sleep

Sleep is closely related to the circadian rhythm, as the quality and length of

sleep follow the body temperature - yes, the lower the temperature, the better.

The need for sleep varies from person to person, but a minimum of 5 hours of

uninterrupted sleep is said to be necessary to maintain performance. However,

the time you sleep is more important than how long you sleep.
Flight Theory PPL(A)(UL)/LAPL Henning Andersen, Midtjysk Flyveskole© 2025 180