What Happens to Your Lungs When Scuba Diving?

Even a quick dip in the pool evokes certain responses in our body, so you can expect a scuba dive to do quite a bit, especially to your lungs and respiratory system.

Your lungs stiffen as you dive due to your dive reflex that redirects blood to this area to conserve energy. This, along with the increase of pressure and decreased volume of air in your lungs, makes it more difficult to breathe oxygen efficiently.

This is a run-down version of how diving affects your lungs, but understanding the full scope of the change can help you dive safely through preparation and recognition of issues. Keep reading as we explore these changes, symptoms of diving related lung injuries, and explain how divers are proactive with these concerns.

Contents hide

1 Is Scuba Diving Good for Your Lungs?

2 Why Do Lungs Hurt After Scuba Diving?

2.1 What Does Lung Squeeze Feel Like?

2.2 How Do You Recover From Lung Squeeze?

3 Signs of Lung Injury After Scuba Diving

3.1 Headache

3.2 Vertigo

3.3 Chest Pain

3.4 Weakness (Paralysis or Partial Paralysis)

4 Do Scuba Divers Have Bigger Lungs?

4.1 How Do Scuba Divers Increase Lung Function?

5 Why Do Scuba Diver’s Lungs Not Collapse?

6 References

Is Scuba Diving Good for Your Lungs?

Scuba diving can be good for your lungs if you respect the need to condition your body, but attempting a dive without proper preparation or respecting the limits of your body can lead to lung injury or long-term concerns.

In a perfect world, scuba diving encourages you to find ways to breathe oxygen with more efficiency, but diving once won’t offer that benefit. Instead, you need to exercise your lungs out of the water to garner the muscle memory needed to breathe efficiently during a dive.

Failing to do this can dash any expectations you had for your dive by using up your air too quickly or causing painful and concerning injuries.

Why Do Lungs Hurt After Scuba Diving?

While we’ll dig deeper into more serious lung health concerns in the next section, it’s not uncommon for your lungs to hurt after scuba diving. Even those who maintain regular breathing exercises may run into these issues, and it ties directly to your body adapting to a new environment.

Your lungs are under more pressure when underwater, and this only increases the deeper you go. While you can work on efficient breathing to keep you calm and maximize your dive time, it doesn’t accommodate for operation under different pressure.

This, combined with the stiffness of your lungs as blood pools to the area, puts more stress on the surrounding muscles. The pain becomes more apparent when you return to your normal air pressure on land.

This hurt should lessen over time if you dive regularly, but expect soreness when you start out or return to diving after a long break.

What Does Lung Squeeze Feel Like?

Lung squeeze, also known as pulmonary barotrauma (PBT) or chest squeeze, is damage or injury to your lungs related to the increased pressure from a dive. It’s a condition unique to breath-hold diving that does not make use of a breathing apparatus.

Freediver Peter Scott said that his experience with PBT left him with the “distinct feeling that [his] lungs were coated from the inside with blood” because he could not breathe well enough to swim on his own. This experience was accompanied by other common symptoms of PBT, including:

Feeling of fluid in lungs
Intense coughing (including coughing up blood)
Wheezing and shortness of breath
Extreme fatigue
Tightness in the lungs
Pain in the chest area

Lung squeeze affects everyone differently. While someone may recover in a matter of hours, another individual can suffer trauma so severe it causes death.

How Do You Recover From Lung Squeeze?

Most divers recover from lung squeeze, but this doesn’t mean they’re in the clear. Recurrence is a common issue following the initial trauma, especially if you don’t take care of your body.

While preventing PBT is much more effective, recovery involves:

Recognizing the issue as soon as possible and ceasing physical activity
Immediate rest (possibly with 100% medical oxygen)
Fluid intake (if airway is secure)
At least 2 weeks without diving or physical activity

Those that suffer from lung squeeze should always consult a medical professional, ideally one experienced with diving-related conditions. A seemingly mild case can easily take a turn for the works, and a physician can let you know when your lungs are strong enough to return to diving with minimal risk.

Signs of Lung Injury After Scuba Diving

The symptoms listed below may seem common, but they’re early signs of dangerous lung injuries that divers face after their time underwater.

While pain in the lungs is the most obvious indicator of injury, these signs can occur at any time and still warn of a major issue.

Headache

A headache after diving warns that part of your body is not working properly. Breathing efficiency and lung injury are a common concern, but headaches are also a symptom of:

Dehydration
Heat stroke
DCS II

A mild headache may only require monitoring, but more severe issues are usually paired with neurological symptoms, immense pain, nausea or vomiting, or a change in mental status.

Vertigo

It’s important to recognize the difference between vertigo and dizziness. Vertigo strictly refers to the feeling that everything is spinning, and if it happens during or after a dive, you can assume a relation between the two.

Vertigo is a common symptom of DCS issues, as well as breathing impure oxygen or suffering an imbalance in ear equalization. Persistent vertigo indicates a more serious condition, and you should visit an ENT before attempting another dive.

Chest Pain

Chest pain is a common indication of PBT, especially when accompanied by the symptoms listed in the section above. Another issue to look out for is pain or discomfort when you swallow.

If your chest pain stays to one side, feeling sharp or tight, it may be a collapsed lung (pneumothorax). This condition is often accompanied by shortness of breath, rapid heart rate and breathing, coughing, fatigue, and bluish skin.

Weakness (Paralysis or Partial Paralysis)

While paralysis is an obvious message that something is wrong, weakness or partial paralysis should also catch your attention. This happens most often in your extremities, and it points towards Type II DCS.

Weakness can be a sign of an arterial gas embolism (AGE) that occurs when nitrogen bubbles form in your tissues and bloodstream. It can lead to bloody froth from your mouth or nose and convulsions, but the most common sign is loss of consciousness.

Do Scuba Divers Have Bigger Lungs?

Scuba divers do not have bigger lungs. Most who ask this question want to know if scuba diving increases total lung capacity, a metric that refers to the most oxygen your body can use. This is a set standard and therefore cannot be increased.

Instead of increasing lung size or attempting to take in more air, scuba divers focus on improving their lung function. This improves the body’s ability to oxygenate blood and remove harmful gasses, and it allows for more efficient use of your scuba gear while underwater.

How Do Scuba Divers Increase Lung Function?

In order to increase lung function, those serious about scuba diving perform certain exercises out of the water to become more efficient at breathing. This allows them to:

Remain calm under water
Use less air
Spend more time on their dive
Limit the risk of lung injury

Divers use diaphragmatic breathing to draw air deep into the lungs where it is handled with greater efficiency. Most of the gas exchange occurs in the lower ⅓ of the lungs, and using the diaphragm to suck air to this area allows divers to breathe less frequently while increasing gas exchange.

They must practice this out of the water to make it effective during a dive, focusing on retraining their diaphragm to expand the area and suck air deep.

Staying in shape is key to improving lung function, especially when divers focus on cardiovascular exercises to improve circulation and efficiency.

While yoga is not considered a traditionally intense workout, it works well to acclimate divers to segmented breathing. By dividing the process of inhaling and exhaling, divers get a better understanding of how to use different muscles and how to use smaller sections of air.

Why Do Scuba Diver’s Lungs Not Collapse?

A collapsed lung is not impossible underwater, but it happens far less often than you would think. The key to preventing a collapsed lung is balancing the pressure inside of your lungs with the surrounding environment.

This is why you follow rules such as:

Never holding your breath underwater
Ascending slowly (usually at a rate of <30ft/minute)
Disclosing pre-existing medical conditions
Remaining calm underwater

A collapsed lung happens most often when a diver holds too much air in their lungs as they ascend. The volume of the air increases, rupturing the thin tissues surrounding the lungs and allowing air to escape.

While your lungs are much more sensitive underwater, following proper diving procedures and focusing on safety allows you the best chance at an enjoyable dive.