Padangbai divig

Don’t Wait, Hydrate!

Let us assure you right at the beginning - the urge to pee during scuba diving activities is physiologically normal. For some people, particularly the beginners, this can be not so pleasant experience which might lead them to believe that they have bladder issues. The inexperienced may even try to deter from drinking enough water before the dive which is a mistake and still makes the urge to urinate even stronger. On one hand peeing while diving is body’s natural reaction, on the other hand however peeing in your wetsuit is not so cool. But let us address that issue another time.

Drinking and Scuba Diving

We have already established that the urge to pee isan expected physiological reaction. But what are the reasons behind?

Human Circulatory System while diving

To put it simply human body is filled with a lot of blood. Hydration and other factors affect the volume of blood in the body, but human circulatory system has its own way to keep a constant volume of blood all the time. It is part of natural adaptability skills to prevent the heart from exploding when it has to contain more amount of blood than it can handle. With every increase in blood volume, the additional amount flows through your veins to the heart. To handle more amount of blood than usual, chambers (atria) of the heart start to stretch. Without any counteract reaction the heart will stretch too far and eventually burst. Your nerve sensors in atriatherefore trigger series of reactions to increase theproduction of urine in the kidneys. When you urinate the body has less amount of fluid to handle and goes back to normal. Just like millions of other activities inside a human body, it happens without you even realizing it is happening. 

Immersion Diuresis on fun dives

Every diver experiences something called a ‘cold water immersion diuresis”. As soon as you jump into the cool water, there is a significant heat loss in the body. To compensate for this loss, blood vessels constrict to retain good temperature in the body. Due to this constriction, there is a sudden increase in the blood pressure. Although the volume of blood in the heart does not increase, your body still detects the increased blood pressure and inhibits ADH (antidiuretic hormone), hence rapid production of urine. 

Weightlessness and scuba diving

The same physiological phenomenon occurs when the body is in near-weightlessness environment. Similar to what the space does to the astronauts, water has natural buoyancy to make the diver fly in the water. Weightlessness also triggers blood flow to the core of the body. Such fluid shift was first detected in astronauts who had to urinate more often than normal. Natural buoyancy mimics (albeit partly) weightlessness caused by the absence of gravity in space experienced by astronauts.
In conclusion, the urge to urinate while diving is a normal reaction of the body to a different environment. Our physiological functions need to make quick adjustments and this includes the release of body fluids through a frequent urination.
However there is another important topic we have been asked about at the OK Divers in Padangbai. When and how to pee during the dives with a wetsuit on and all the divers around? Is it even right to pee in the wetsuit especially if it’s not yours? What are the dos and the don’ts? We will address these questions in our next blog post. Stay tuned.

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