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The adrenal gland -

Adrenaline is produced in the medulla in the adrenal glands. The adrenal glands sit above the kidneys.

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Release of adrenaline -

When a stressful or dangerous situation occurs, your heart is likely to race, your hands begin to sweat, breathing becomes more shallow, and you instinctively start looking for an escape, a way out of your plight.

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Hypothalamus -

When this happens, your hypothalamus, part of the limbic system at the brain's base, activates the sympathetic nervous system. This is also known as the "fight-or-flight" response—an automatic physiological reaction to an event that is perceived as stressful or frightening.

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More adrenaline -

This response in turn prompts the brain to instruct the adrenal glands to produce more adrenaline.

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Redirecting blood -

Adrenaline is released throughout the bloodstream, where it triggers blood vessels to contract and redirect blood toward major muscle groups, including the heart and lungs.

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Pounding heart -

This rush of adrenaline is one of the body's vital defense mechanisms and prepares the body for fight or flight. The first indicator of an adrenaline rush is increased heart rate, the 'pounding' commonly associated with elevated levels of fear or stress.

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Extra oxygen to the lungs -

In reaction, the rush sends extra oxygen to the lungs, for example to aid a person to run away from a threat.

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Increase in strength -

Adrenaline redirects blood towards the muscles, temporarily increasing strength.

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Pain inhibitor -

Besides inducing a sense of power and vigor, adrenaline can temporarily inhibit the body's ability to feel pain.

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Shallow breathing -

With various muscle groups grabbing all the oxygen, breathing can become shallow and rapid as we take in more oxygen, preparing to bolt if we have to.

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Increased alertness -

Similarly, a sudden rush of adrenaline can help you think on your feet and focus the mind—very useful if you need to plan a quick retreat from a potential threat.

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What are the side effects? -

Sweating as a result of stress or anxiety is a common side effect of an adrenaline rush.

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Dilated pupils -

Another side effect of adrenaline is the widening, or dilation, of the pupils to let more light enter the eyes, thus improving vision.

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Feeling lightheaded -

But the change in blood and oxygen supply can leave you feeling lightheaded.

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Nonphysical stressors -

Rushes of adrenaline can also be the result of nonphysical stressors, such as relationship troubles or financial worries. 

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Sleep problems -

In fact, too much adrenaline is detrimental to our physiology. The changes it causes in the body can become problematic and uncomfortable. Disruption to sleep patterns is one adverse effect. Issues with digestion and hormone regulation can also occur.

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Persistent surges of adrenaline -

Over time, persistent surges of adrenaline can increase blood pressure, damage blood vessels, and elevate the risk of heart attacks or stroke.

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Stress levels -

Stress alone is a well-documented cause of adrenaline rushes.

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Post-traumatic stress disorder -

According to the UK's National Health Service, studies have shown those with post-traumatic stress disorder (PTSD) can experience adrenaline rushes from memories or thoughts about trauma, typically victims of combat or assault.

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Perceived threat -

Furthermore, people with PTSD have been found to continue to produce high amounts of fight-or-flight hormones even when there's no danger and any threat has long passed.

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Seeking out an adrenaline rush -

There are those, of course, who thrive on an adrenaline rush. Extreme sports enthusiasts, so-called adrenaline junkies, often go great lengths to achieve their high, not least skydivers. In fact, skydiving is one of the biggest adrenaline rushes a human can experience.

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Watching a horror movie -

According to Forbes, the ultimate horror movie is 'Sinister' (2012), starring Ethan Hawke. A study concluded that the heart rates of participants in a test audience peaked at 86 beats per minute while watching this film, the highest figure recorded from the 50 highest-rated horror movies included in the experiment. That's a frightening level of adrenaline!

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Bungee jumping - Bungee jumping is another well-known adrenaline pumping past time. Actually, pregnant women, people with heart problems, and those with high blood pressure are not advised to participate in this stomach-in-mouth action-filled recreational activity.

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Extreme white water rafting - White water and adrenaline have long gone hand in hand with each other.

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Cage-diving with sharks -

Making yourself available as potential lunch for a great white shark is a guaranteed adrenaline rush!

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How to control adrenaline -

For all its exciting connotations with adventure sports, there are still those who'd rather maintain control over their adrenaline levels. One way of doing this is to learn techniques to counter your body's stress response. Exercise is a great leveler, and yoga or tai chi exercises, which combine movements with deep breathing, help promote equilibrium in the body, and allow your body to rest and repair itself.

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Meditation -

In fact, the rest-and-digest response serves as a direct answer to the fight -or-flight option. Meditation works in the same way as yoga in that is provides mind and body with the balance needed to counter any potential adrenaline rush.

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Avoid the cellphone -

Resist the temptation to browse your mobile device right before bedtime. The same goes for computers and TV, where too much blue light can make you anxious, stressed, and depressed. And as for listening to loud music through headphones before trying to get to sleep? Well that's a no-brainer, isn't it?

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In an emergency -

If you're caught by surprise by a rush of adrenaline, breathing into a paper bag can balance the oxygen supply to the body. This slows down oxygen intake and can help reduce feelings of dizziness. It may also help a person calm down and feel more in control.

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Word association -

Another great self-help idea to combat an unwanted adrenaline rush is to chose and repeat one specific word that is calming and meaningful. This can help focus the mind and distract the body from adrenaline's negative effects.  

Sources: (Healthline) (Psychology Tools) (Harvard Business Review) (NHS) (Forbes)

See also: Does blue light have a dark side?

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