Adrenaline: only surfers know the feeling | Photo: Ed Grant

Adrenaline, medically known as epinephrine, is released into the bloodstream from the medulla in the adrenal glands when surfers ride intense waves. So, is it good or bad to be an adrenaline junkie?

Adrenaline is a fantastic hormone. As danger and fear are activated in human's brain, adrenaline bursts invade almost all body tissues and change the way muscles behave.

When surfers put their life in danger - especially in big wave surfing conditions or dangerous wave peaks - their bodies ignite the so-called fight-or-flight response, a reaction to the information transmitted to the nervous system by your senses.

As adrenaline reaches the final target, muscles work in order to perform respiration at an increased rate to improve strength and resistance. Survival mode is, somehow, triggered so that all your systems get ready to protect life.

Adrenaline was isolated from the adrenal glands of sheep and oxen, for the first time, in 1901, by the Japanese chemist Jokichi Takamine. In the last 100 years, scientists discovered that adrenaline has impact in several human organs.

Epinephrine increases heart rate and respiratory rate, and promotes vasodilatation. At the same time, adrenaline stimulates glycogenolysis in the liver and triggers lipolysis to burn fat. Muscle contraction accelerates breathing.

It has been proved that adrenaline is positive in surfers. The pumped-up sensation felt before or immediately after an extreme surfing moment happens when the surfer's body releases dopamine to act like a natural pain killer.

Surfing demands a balanced aerobic and anaerobic system exercise. When you're paddling, oxygen is vital (aerobic). When you're taking off and riding the wave, you're ordering and consuming energy and muscle power (anaerobic).

It is possible that you'll burn less fat. Anaerobic sports produce lactic acid, which blocks adrenaline's fat consumption properties.

Water is health and surfing is one of the most complete sports. But be careful. Adrenaline junkies, as described in the iconic surf movie "Point Break," can suffer exhaustion, irritability and restlessness due to adrenaline withdrawal.