Once in a while, if you don't drink enough water before you exercise, you might get a headache caused by dehydration. However, if you start having headaches during or after exercise more often, it could mean something else.
If your head starts pounding after you work out, climb a flight of stairs or even have sex, you could be experiencing what's called an exertional headache.
"Exertional headaches may be simple headaches caused by exercise," says Zubair Ahmed, MD, a neurologist and headache specialist at the Cleveland Clinic's Center for Neuro-Restoration. "These are called primary exertional headaches."
"Less commonly, they are caused by a more serious medical condition, such as a brain aneurysm or brain tumor," Dr. Ahmed says. "These are called secondary exertional headaches, and it is important to find the cause of these headaches."
Primary Exertional Headaches
Primary exertional headaches usually occur after strenuous exercise, like climbing a long flight of stairs, running, swimming or working out at the gym, notes the Mayo Clinic. The cause of these headaches is not known, but they are not dangerous and can be treated with medication. Symptoms are:
- A pounding headache that occurs during or after exercise.
- A headache that affects both sides of your head.
- No other symptoms other than the headache itself.
The National Headache Foundation says that 90 percent of exertional headaches are the primary type. People with these headaches may also be at risk for migraine headaches. The Mayo Clinic notes that these headaches are more common if you are exercising in hot weather or a high altitude or if you have a personal or family history of migraines.
There are several medications that may help. "Primary exertional headaches are often treated successfully with indomethacin or propranolol," Dr. Ahmed says. Indomethacin is a nonsteroidal anti-inflammatory drug (NSAID), and propranolol is a beta blocker drug. Beta blockers slow the heart rate and lower blood pressure. Propranolol may be used before exercise to prevent these headaches, according to the Mayo Clinic.
Secondary Exertional Headaches
About 10 percent of exertional headaches are caused by conditions that include aneurysm, brain tumors or abnormal blood vessels in the brain, the National Headache Foundation says. The Mayo Clinic adds bleeding in the brain as another possible cause, and notes that symptoms of a secondary exercise headache are similar to those for a primary type but may have these warning signs:
- A more severe and longer-lasting headache.
- Vomiting with the headache.
- Stiff neck.
- Double vision.
- Loss of consciousness.
Evaluating Exertional Headaches
"Because a few exercise headaches can have a serious cause, it is important to let your doctor know about any headaches that occur during or after exercise," Dr. Ahmed says. "Your doctor may order an imaging study of your brain to rule out a secondary cause.
Imaging studies of the brain, like an MRI or CT scan, may be recommended if you have exertional headaches that last more than a few hours, you are over age 40 or you have headaches that come on very suddenly, called a "thunderclap" headache, according to the Mayo Clinic.
If a secondary cause is found, treatment may include surgery if the cause is an aneurysm or a tumor, the National Headache Foundation says. An aneurysm is a blood vessel that has a weakened wall that balloons outward. The aneurysm may start to bleed during exercise. Warning signs could include a sudden severe headache, double vision, stiff neck and loss of consciousness.
The foundation also gives warning signs for a secondary exertional headache caused by a brain tumor. A brain tumor causes headaches that get gradually worse and more frequent over time. There may also be forceful vomiting (projectile vomiting), speech problems, changes in balance or clumsiness, changes in personality or seizures.
Preventing Exertional Headaches
If your doctor determines that it's exertion that's causing your headaches, that these are in fact primary exertional headaches, the Mayo Clinic suggests these tips for preventing them:
- Ask your doctor if you should take medication before exercising.
- Avoid exercising in hot and humid weather.
- Avoid exercising at high altitudes.
- Do some light warming up before starting to exercise.
- Avoid exercises or activities that seem to trigger your headaches.