Fatigue implies a reduction in the body’s capacity and therefore results in the use of different physiological mechanisms with a higher cost, in order to maintain the same level of activity
Being tired means having to use more resources to achieve the same result
Muscular fatigue is the result of the internal energy resources in the muscles being exhausted, an increase in acidity, and the fact that blood circulation is not able to evacuate waste and provide the glucose and oxygen that are needed
Nervous fatigue is when the nervous system is no longer able to sustain information processing at the same pace
It results in an increase in errors and omissions and a deterioration of perception
It can also give rise to signs of irritability
Initially, one is not aware of fatigue
Although their capacities are affected, the person does not realize it
At a later stage the person notices the fatigue and may implement strategies to manage it (asking for help, double-checking)
From a safety point of view, the ‘unaware’ stage of fatigue is particularly critical