Adrenaline
Adrenaline is a hormone produced by the adrenal glands during high stress or exciting situations.
This powerful hormone is part of the human body’s acute stress response system, also called the “fight or flight” response.
It works by stimulating the heart rate, contracting blood vessels, and dilating air passages, all of which work to increase blood flow to the muscles and oxygen to the lungs.
The Adrenal Glands
The adrenal glands are found directly above the kidneys in the human body, and are roughly 3 inches (7.62 cm) in length.
The Fight or Flight Response
The term “fight or flight” is often used to characterize the body’s reaction to very stressful situations.
It is an evolutionary adaptation that allows the body to react to danger quickly.
Dilated air passages, for example, allow the body to get more oxygen into the lungs quickly, increasing physical performance for short bursts of time.
The blood vessels contract in most of the body, which redirects the blood toward the heart, lungs, and major muscle groups to help fuel the reaction.
When a person encounters a potentially dangerous situation, the hypothalamus in the brain signals the adrenal glands to release adrenaline and other hormones directly into the bloodstream.
The body’s systems react to these hormones within seconds, giving the person a nearly instant physical boost.
Strength and speed both increase, while the body’s ability to feel pain decreases.
This hormonal surge is often referred to as an “adrenaline rush.”
Side Effects
In addition to a noticeable increase in strength and performance, this hormone typically causes heightened awareness and increased respiration.
When there is stress but no actual danger, a person can be left feeling restless and irritable.
This is partly because adrenaline causes the body to release glucose, raising blood sugar, and giving the body energy that has no outlet.
Work Out
Many people find it beneficial to “work off” the adrenaline rush after a particularly stressful situation.
In the past, people handled this naturally through fighting or other physical exertion, but in the modern world, high-stress situations often arise that involve little physical activity.
Exercise can use up this extra energy.
Though adrenaline can play a key role in the body’s survival, it can also cause detrimental effects over time.
Prolonged and heightened levels of the hormone can put enormous pressure on the heart muscle and can, in some cases, cause heart failure. Additionally, it may cause the hippocampus to shrink.
High levels of adrenaline in the blood can lead to insomnia and jittery nerves, and are often an indicator of chronic stress.
I have no explanation and I hope these explain why I was feeling restless and irritable for days at times and why I am suffering from insomnia for days at times when there was no traumatic event happening in my life.