A burning sensation in your lungs when running is not uncommon, but it's something that deserves attention.
It's a sign that your body's not happy about something, and whatever the cause, over time it could worsen and become chronic. Plus, it's likely to discourage you from getting your run in, which is hardly ever a good thing.
You may experience lungs that are burning when running due to a variety of reasons, including acid reflux, asthma or a respiratory infection.
Read more: How to Improve Lung Capacity for Running
Cold, Dry Air Can Burn
One of the more common — and harmless — reasons your lungs burn when running is that your body must work harder to humidify air to 100 percent and warm it to body temperature before it gets into your lungs.
The cells that line the trachea become irritated as they give up their water to humidify the air, which may cause a burning sensation in your chest and throat. There's only so much you can do to prevent this, but staying hydrated helps. Also, you might slacken your pace a bit. Panting for air causes the tissues in your airways to dry out even more.
New to Exercise?
If you're out of shape and have been sedentary for awhile, you may feel a burning sensation in your lungs as your body gets used to the idea of breathing harder and stretching in ways that are unfamiliar. Breathing harder causes the intercostal muscles that connect the ribs to stretch in ways that your body may tell you about.
Plus, your lungs themselves are expanding and contracting with a vigor that is waking up their natural flexibility. Once again, the solution may be to back off and not push yourself so hard. Build up your runs (and the rest of your routine) day by day and week by week. That gives your body time to adjust to its new management. Ace Fitness says to "start low and go slow": meaning to exercise at a lower intensity and to not try and be a star right off the bat.
Digestion and Acid Reflux
Acid reflux occurs because of a weakness or dysfunction in the muscular band that separates the stomach from the colon. When this band fails to form a tight seal after swallowing, acidic digestive juices can splash upwards into the esophagus and even as far as the throat and mouth.
The tissues in the organs above the stomach are easily injured by these acids, which result in nerve irritation that can cause a burning sensation in the chest area. In extreme cases, digestive acids can actually get into the lungs, irritating its tissue and causing a burning sensation. Sometimes it can make breathing difficult. This is a very serious condition and one that can lead to a condition called aspiration pneumonia.
Aspiration — that is, digestive acids getting into your lungs — is relatively rare. But acid reflux, which in its severe and chronic form is called gastro-esophageal reflux disease, or GERD according to Mayo Clinic, crosses symptoms with a lot of other things.
Because the peripheral nerves of the esophagus connect well into the solar plexus, they spread the word around the whole chest region when they get irritated. GERD can even make people think they're having heart attacks.
When you're running, acid splashes up into tissue that's probably already irritated from previous exposure. The gravitational impact of running causes the contents of your stomach to splash upward, and since your esophagus isn't corked properly, all that tissues gets irritated. So the burning may feel like it's in your lungs but really it's coming from elsewhere.
Whatever the case, chronic acid reflux is usually treated with acid blocking drugs called PPIs, which are sold over the counter under the brand names such as Nexium, Prilosec and Prevacid. These are available over the counter but doctors may prescribe them for longer periods of time and at higher doses.
If one round of a PPI doesn't knock the problem, it's a good idea to check in with your doctor. You should also avoid eating three hours before running and also before bedtime.
Running and Asthma
Asthma is a chronic lung disease that causes the airways to become inflamed. This makes it hard for oxygen to penetrate your lungs and get into your bloodstream. Asthma causes wheezing, tightness in the chest, shortness of breath and coughing — all of which certainly could add up to a burning sensation says ACE Fitness.
Take note of any environmental factors that may have occurred. Have you just recently taken up running? It's possible that this new exertion is unmasking a condition that was already there.
Asthma may have different causes. One of them could be running itself, or any other vigorous aerobic exercise. This is known as exercise-induced asthma, and it's one of the more common forms of asthma experienced by runners.
Exercise may set off asthma or make it worse because faster respiration cools the airways but also dries them out. As the air passages then narrow as they warm back up. Exercise-induced asthma is most prevalent when it's cold and dry, which for most people is fall and winter.
However, people who experience asthma usually have multiple triggers, which can be hard to pinpoint. It may be, for example, that you're allergic to a certain pollen and that running boosts your exposure into the red flag zone. Mucus in the airways can trigger a burning sensation, so if your allergies are really set off, mucus production kicks in and stirs up its own mischief.
Asthma is a serious condition and in severe cases can require hospitalization. It's treated with a variety of medications depending on its cause, severity and frequency.
Cold or Flu
If you've had a respiratory infection such as the cold or flu, keep in mind that those symptoms may linger for weeks after the bug's onset. If you're recovering from a nasty cough and return to running after your illness, the burning may be due to strained muscles and ligaments in the rib cage. In addition, your lungs themselves may also be somewhat inflamed from the illness.