Cortisol is a steroid hormone produced by the adrenal cortex. Its elevated levels may be responsible for, among other things, a negative:
- Increase in glucose (inhibits consumption) and acceleration of glucogenesis
- Increased blood pressure and vasoconstriction
- Increased protein catabolism – releases free radicals and amino acids, slows their absorption by muscles
- Retention of salt in the body and greater excretion of potassium
This is why falling asleep after an evening workout is so difficult: more glucose is supplied to the brain and it cannot calm down, while the muscles suffer from pain and general signs of overtraining. We find it harder to fall asleep, which means it is also harder to enter nocturnal catabolism – regulated by its own rhythm and responsible for the body’s energy during long hours without food. At the same time, cortisol stimulates our appetite…
As a result, stress comes back with redoubled force – the chasing thoughts have even more glocose ‘fuel’ and the body cannot relax properly. Stress therefore exacerbates the negative effects in a training context: elevated cortisol not only limits muscle growth, but also promotes the development of fat tissue (insulin economy).
Fat tissue is primarily deposited around the face, neck and torso.
People with elevated cortisol also often struggle with mood disorders, compounded by sleep problems and even depression.