Why You Get a Headache After Swimming (And What to Do About It)

Triathletes are no strangers to headaches due to poor bike fit, dehydration, and overexertion. But when frequent headaches after swimming keep you out of the pool and open water, finding a solution to the disruption can put your training back on track.

A headache is a common ailment and cause of visits to the emergency department, urgent care, and family physicians. Most of the time, headaches resolve on their own and are not the result of anything serious. Exercise can bring on headaches, but that doesn’t mean you need to stop that form of exercise entirely. Instead, looking at the nature of the headache can help you get to the root cause to prevent it.

This is particularly true for swimming-related headaches that occur primarily due to the nature of the activity itself, related to the equipment, mechanics, or swimming environment. We’ll look at three common swimming headache causes as well as prevention methods so you can enjoy your training.

How swimming equipment can cause headaches

While we don’t often think about swimming being an activity associated with a lot of equipment, there are a couple of items that swimmers use that can contribute to the development of headaches: the swim cap, goggles, and earplugs. Specifically, if those implements are too tight, they can compress against the scalp or face, leading to a headache.

Fortunately, opting for a looser swim cap or loosening your goggle straps is a quick remedy. If your goggles leak when you loosen the straps, then chances are you need to change to a different model that fits your facial features better. Triathlete’s editors regularly test and review the best triathlon swim goggles to bring you an annual list.

Another issue related to the goggles can be “swimmer’s headache,” otherwise known as supraorbital neuralgia. The supraorbital nerve exits the bones of the face above the eye and passes through a notch as it passes upward over the forehead and scalp. (You can feel the notch on yourself in or just below the eyebrow about a third of the way from the mid-point of your face.)

Goggles that impinge forcefully on this notch may cause pain in the distribution of the nerve, over the forehead and scalp, and it may even feel as though your hair hurts. Loosening your goggles or finding a pair that is a better fit for your face can resolve this.

The last piece of equipment that may cause headaches for swimmers is earplugs. When earplugs are too large, they can cause headaches. Switching to better-fitting, swim-specific earplugs can address the issue quickly and effectively.

Why swimming mechanics can cause headaches

The mechanics of swimming can also result in headaches. Flip turns can contribute to headaches after swimming. Some people are very sensitive to the tumbling motion that is part of a flip turn at the end of each length of the pool, and in these instances, vertigo and, on occasion, headaches, may result. Modifying your technique to use open turns instead of flip turns may be all that is needed to remedy things if this is your issue.

The environment that we swim in can also contribute to headaches. This is especially true for those of us who swim in indoor pools that may have a higher concentration of chlorine because of ventilation issues. Chlorination of pool water is necessary for maintaining a sanitary environment, but some people are more sensitive to the chemical than others. In those who are particularly sensitive, the chlorine may cause swelling and inflammation of the mucosa within the nose, and this can obstruct the sinuses, resulting in a buildup of pressure within them and a dreadful sinus headache.

This is not an infection, but rather a local inflammatory reaction to chlorine. Antibiotics are not needed to treat this problem, but there are a couple of options that you can try. The first is using a nose plug, which prevents water ingress into the nose and the mucosa from becoming inflamed. While a simple solution, some athletes find nose plugs uncomfortable, and not everyone likes using them.

An alternative is to use a nasal steroid spray, which is available without a prescription. Use it before and after swimming to help diminish any chlorine reaction. As with all medications, consult your physician to determine if this is the right option for you.

Whether you swim indoors or out, in chlorinated pools or natural bodies of water, another potential cause of headaches for swimmers is an infection of the outer ear canal, colloquially known as swimmer’s ear. This entity, more formally known as otitis externa, can be very unpleasant and often causes headaches along with ear pain and drainage. It is treated with antibiotic ear drops, and in those who are susceptible, may be prevented with properly fitted earplugs.

When surrounded by water, you might be less likely to drink water

Although it may seem counterintuitive since you are immersed in water when swimming, prolonged swimming is quite dehydrating. Dehydration can cause headaches, so ensuring proper fluid intake, especially during long swim workouts, is just as important as maintaining fluid intake when biking or running.

Finally, swimming, like any form of exertion, may cause a primary exercise-induced headache. These are headaches that come on during or immediately after exertion, are throbbing in nature, and can last as long as 24 hours. The treatment for this is rest and analgesics.

When to see a doctor for a headache

While most swimming-induced headaches are benign and easily managed, it is important to recognize the features of headaches that require a higher degree of concern and more prompt evaluation. Any headaches associated with a fever and stiff neck, nausea and vomiting, neurological signs and symptoms, including seizures, and those that come on like a thunderclap or are associated with head injury are particularly worrisome. If you are ever unsure about a severe or recurring headache, see your doctor.