When you rise, the air in your lungs becomes dangerous. Holding your breath as you climb to the surface causes your lungs and the air within them to expand when the water pressure decreases. Because that air has nowhere to go, it continues to bulge against the walls of your lungs, despite the organ’s limited capacity. This can lead to damage, even death, if you stay under for too long.
The danger of this condition is heightened by the fact that you cannot breathe out while underwater. So if you fill up with enough air that it begins to hurt when you take a deep breath, you need to get out of the water immediately so you don’t pass out from the pain.
People who have this fear often are advised not to breathe in any more than an average person would at a depth of 10 meters (33 feet). Even then, they should avoid taking a full breath or holding it for more than a few seconds at a time. Instead, they should take small breaths through their mouth or nose to keep air flowing into their lungs.
This is necessary because the more air you take on down below, the harder it will be to get back up to the surface. You will need plenty of oxygen down there to be able to come up for air, but the more air you take in, the less oxygen will be available for your body to use. This is why people who suffer from this fear are advised not to hold their breath for more than a few seconds.
Excessive lung expansion can also result in air bubbles in your circulation or too much strain on your heart, both of which can be deadly if not treated. As long as you release the breath you have held at a steady rate, you should experience no ill effects from this activity.
The main reason why divers don’t hold their breath for prolonged periods is that it’s uncomfortable. You body tries to compensate by increasing the breathing rate. This means that even though you aren’t taking in more oxygen than normal, you are using up more of it per minute. The human body was not designed to operate like this for long periods of time.
Another reason why divers do not hold their breath is because it’s unsafe. If you stop breathing, you will eventually run out of oxygen and die. Divers therefore keep their breaths shallow so they can continue to breathe for as long as possible without risking death. The more time you can spend under water the more chances you have of finding treasure.
At the end of a dive, when returning to the surface, you will usually take a single deep breath before blowing off the accumulated gas. This allows any remaining air in your lungs to leave your body and prevents your filling your lungs with more air than is safe over time.
Why do scuba divers need to exhale air when they climb to the water’s surface? External pressure falls when a diver ascends to the surface. If the air in the lungs was not expelled, its volume would increase, causing significant damage to the lungs. The pressure in the lungs must alter in response to changes in external pressure. When the diver rises toward the surface, the internal pressure decreases, which causes more air to be released from the lungs.
The amount of air that can fit in the lung is called “functional residual capacity”. This capacity is determined by many factors, but mostly by the size of the chest cavity and the tension of muscles surrounding the chest area. At any given time, some of the air in this space is still trapped within blood vessels or other parts of the body.
When a diver goes underwater, the external pressure increases, which causes more air to be taken into the lungs. This increased air volume cannot stay inside the chest cavity because there are no valves like those in your heart to let air out again. So it has to go somewhere else - such as the water spouting from the diver’s mouth! The more experienced the diver, the more quickly he/she will ascend because there is less air left in his/her lungs. This is why new divers have to breathe slowly so they don’t overexert themselves and cause damage to their lungs.
Because pressure flattens hundreds of gas bubbles, your wetsuit becomes thinner and holds less water. When you rise, you quickly regain the buoyancy of your wetsuit and BC. As a result, you must be aware of buoyancy changes whenever you change depth, and especially when ascending. If you don’t, you will sink.
The first thing to understand about adjusting your buoyancy is that you have two options: lift more or lift less. You can’t do anything in between. If you try, you’ll float up too fast or not fast enough to stay safe. So, for example, if you go down 10 feet and know you’ll need 30 minutes at that depth to finish your dive, then you should plan to lift 30 times during that time period - once every minute.
If you only have time to lift 20 feet in 30 minutes, then you should plan to lift twice as much as before - 5 lifts instead of 2. Keep in mind that all things being equal, lifting more will make it harder to stay under control, so use caution not to overshoot your target depth.
Finally, if you want to raise your body temperature while diving, either wear wet clothes or dry out after each dive. Wearing wet clothes increases your heat loss, while drying out reduces it.
The Human Body and Water Pressure When you dive deep into the water, all of the water around you compresses your diaphragm. This, in turn, inhibits you from taking a breath of fresh air. That’s how diving too deep with a snorkel feels. You may even hear someone else’s lungs filling up with water if they’re scuba diving next to you.
When you come back up for air, the first thing your body does is expand your chest and pull in more air than you actually need. This is because our bodies try to protect us from any sudden changes in pressure. For example, if you were on a plane that suddenly dropped 30,000 feet, your body would react by opening your lungs to allow more oxygen in. This is why astronauts experience “space sickness” when exposed to low pressures for long periods of time; their bodies aren’t used to it.
Your body also tries to protect you from drowning by limiting how much air you can take in through your mouth and nose. This is called an “air limit.” If you go over your air limit, you’ll start to feel dizzy and might even lose consciousness.
The good news is that you can breathe through a snorkel even when swimming underwater! All you have to do is keep your head above water, let out a big breath, and blow it back in again.
Copyright © 2020 - 2026 Sportsmanist Inc.
