Fatigue is physical and mental fatigue.
When physical fatigue occurs, when you continue to work, repeat, exercise, or do something, as a result, your ability to work and exercise has declined.
At this time, the deterioration of quality occurs faster than the decrease in the amount of exercise (muscle).
The reason for the decline in muscle activity is that using muscles for a long period of time decreases the action of the proximal vertebrae, which is a sensory device that can detect muscle contractions, or the end of the motor nerve surrounded by muscles, or blood vessels. The balance of the breathing cycle that sends oxygen to the muscles breaks down.
Therefore, fatigue occurs.
It is the cerebrum that determines this fatigue.
There is always some kind of inhibition at the motor center of the muscle-moving cerebrum.
When muscles get tired, the cerebrum further strengthens its inhibitory power.
As a result, the exercise order becomes sluggish, which reduces muscle activity in the whole body, and causes fatigue symptoms, but this can be said to be legitimate.
Mental fatigue is caused by nervous fatigue, anxiety, discomfort, and anxiety caused by excessive use of sensory organs.
Neural fatigue occurs because when nerves are intensively active, metabolism occurs in nerve cells or synths, causing the balance of active substances to be disrupted and the action of the nerves to be lost.
This also makes you tired of telegraphy.
Psychological fatigue occurs when anxiety or frustration in interpersonal relationships, work, etc. continues, and the old cortex of the brain feels strongly about this and breaks the balance by overreacting the autonomic nerves.
Also, fatigue has acute fatigue and chronic fatigue.
Acute fatigue is a relatively rapid phenomenon of fatigue when carrying heavy things or after a gallop.
It is easy to recover this quickly.
Chronic fatigue is also called accumulation fatigue, and fatigue from one day's activities does not recover enough from sleep, leading to the next day, which builds up and degrades function.
Sleep is the best way to recover from physical fatigue.
Moderate exercise is good for recovering from mental fatigue, and recreation for mood change is good.