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Understanding Adrenaline


You always hear people talking about the "adrenaline rush" of physical activity, and how awesome is feels. But do you know what adrenaline is or what it does? You may find that it's not the chemical you think it is!

What is Adrenaline?

Adrenaline, also known as epinephrine, is a chemical produced by your adrenal glands in response to stress (physical, mental, emotional, etc.). The human body has a natural "fight, flight, or freeze" response, and adrenaline is what gives you the energy to either "fight" or "take flight".

Adrenaline and its sibling noradrenaline are produced in the medulla of the adrenal glands, which are located on top of the kidneys. When they are produced, the adrenal glands release them into the bloodstream, where they travel around the body and convey nerve impulses to the various organs, muscles, and body tissue.

Adrenaline can cause the following reactions:

  • Increased heart rate (meaning more blood flow)
  • Increased blood pressure (the results of increased blood flow)
  • Enlargement of the pupil (to enable the eye to see and respond more quickly)
  • Expanding of the air passages in the lungs (to make it possible to oxygenate the blood more efficiently)
  • Speeding up of the body's metabolism (to produce more energy for the "fight or flight")
  • Redistribution of blood to the muscles (ensuring the muscles have all they need for the coming physical exertion)
  • Maximizing glucose levels (providing the body with quick-acting energy for immediate use)
All of these reactions make it easier for you to either "fight" or "take flight," helping you to react in a stressful situation.

Now, you need to know that there is always some adrenaline and noradrenaline in circulation around your body. These chemicals help to convey signals between nerve cells. However, the levels are low enough to be unnoticed, and you'll only feel that rush of adrenaline in a situation of stress.

How Does This Affect Exercise?

When you are lifting weights, running, or cycling, your body feels like it is under physical stress. The body has been programmed to react when it feels the stress of heavy weights or long-term cardiovascular exertion. It responds by producing more adrenaline, which in turn helps to increase the amount of energy and blood flow available to use.

Strength training will cause adrenaline to be produced and released much more quickly than cardio exercise. After all, you are lifting heavy weights with every set, and your muscles only have so much energy available. Once the intra-muscular energy runs out, your body reacts as if it is under "attack," and adrenaline is flooded into the body to provide it with more energy, oxygen, and blood flow.

When it comes to cardio, the body responds more slowly. The energy is not used as quickly as with strength training, so the production of adrenaline is more gradual. However, those doing sprint training or HIIT training will cause the body to react as if it's in "flight" mode, leading to a surge of adrenaline.

3 Reasons Why You Need 30 Minutes of Cardio a Day to Lose Weight

Some people get lucky and are born with fit, toned bodies. Andy Peloquin is not one of those people... Fitness has come hard for him, and he's had to work for it. His trials have led him to becoming a martial artist, an NFPT-certified fitness trainer, and a man passionate about exercise, diet and healthy living. He loves to exercise -- he does so six days a week -- and loves to share his passion for fitness and health with others.

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