Excessive Phlegm After Exercise

If you are coughing up phlegm after exercising you might need to look into it.
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Crushing your mile time or hitting a new max during a set of deadlifts calls for a celebration. Unfortunately, for some people, this post-workout time is spent ridding their body of excess phlegm. If you're coughing up mucus after exercise, it's time to figure out what's causing it, and how to cope.


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Exercise-Induced Bronchoconstriction

If you're plagued with breathing problems while working out, especially during cardiovascular exercise, you may want to ask your doctor about exercise-induced bronchoconstriction (EIB).


Formerly referred to as exercise-induced asthma, EIB happens when your airways narrow during physical activity, according to the American College of Allergy, Asthma & Immunology. As a result of this narrowing, symptoms such as coughing and shortness of breath can occur both during and after exercise.


EIB can happen to anyone, not just people with asthma. In fact, an August 2018 review published in the NPJ of Primary Care Respiratory Medicine reports that approximately 5 to 20 percent of the general population, those without asthma, have EIB. This means, even if you don't have asthma, you can experience symptoms of EIB both during and immediately following exercise.


This percentage increases significantly in patients with asthma. About 90 percent of people with an asthma diagnosis also have EIB.

Read more: Dry Cough After Running

Respiratory Conditions Cause Phlegm

It's not uncommon to hear a fellow gym-goer hacking up a snot rocket on the treadmill, especially during cold season. After all, many people continue with their regular workout routine even when they are sick.

But if you're at the start of an illness, an excessive amount of mucus during and after exercise may be a sign that you're headed towards a respiratory illness. Pay attention to how you're feeling and note if the extra hacking is something you typically experience while engaging in physical activity.

Whether or not you should continue running, lifting weights or cycling while sick is dependent on your symptoms. In general, the Mayo Clinic says if your symptoms are above the neck, then it's OK to exercise. This means a runny nose, sneezing, a minor sore throat or congestion.

But if those symptoms creep down your body (aka below the neck), it's time to take a break and rest. Certain infections like bronchitis can increase phlegm production, coughing and chest congestion, especially during exercise.

Read more: Why Does Your Breathing Rate Increase During Exercise

Allergic Rhinitis and Excessive Phlegm

If you're susceptible to environmental or seasonal allergies, you may find that coughing up mucus after exercise is a common occurrence. You can trigger an inflammatory process when breathing in allergens like mold, dust and pollen during physical activity.

When this happens, Harvard Health Publishing says blood vessels swell, which causes nasal congestion and an increase in mucus production. And consequently, excessive phlegm both during and after exercise.

One way to minimize the effects of allergic rhinitis is to avoid the allergen. For example, if pollen is the culprit, take your running or cycling indoors when levels are high. If you find there's something in your gym that's triggering a reaction, such as mold, you may need to find another place to work out.

When exercising at home, make sure the room you're using is dust-free — or at least clean — to help reduce symptoms such as nasal congestion and coughing.

While certain exercise conditions can increase phlegm temporarily, without cause for concern, if your symptoms come on suddenly, get worse, or you're worried, consult your doctor.