Exercise headaches occur during or after sustained, strenuous exercise. Some activities associated with exercise headaches include running, rowing, tennis, swimming and weightlifting.

Doctors divide exercise headaches into two categories. Primary exercise headaches are usually harmless, aren't connected to any underlying problems and can often be prevented with medication.

Secondary exercise headaches are caused by an underlying, often serious problem within the brain — such as bleeding or a tumor — or outside the brain — such as coronary artery disease. Secondary exercise headaches may require emergency medical attention.

Primary exercise headaches

These headaches:

• Are usually described as throbbing
• Occur during or after strenuous exercise
• Affect both sides of the head in most cases

Secondary exercise headaches

These headaches may cause:

• The same symptoms as primary exercise headaches
• Vomiting
• Loss of consciousness
• Double vision
• Neck rigidity

Primary exercise headaches typically last between five minutes and 48 hours, while secondary exercise headaches usually last at least a day and sometimes linger for several days or longer.

When to see a doctor

If you experience a headache during or after exercise, consult your doctor. Call your doctor right away if the headache begins abruptly or if it's your first headache of this type.

Primary exercise headaches

The exact cause of primary exercise headaches is unknown. One theory is that strenuous exercise dilates blood vessels inside the skull.

Secondary exercise headaches

Secondary exercise headaches are caused by an underlying problem, such as:

• Bleeding in the area between the brain and the thin membranes that cover the brain (subarachnoid hemorrhage)
• Abnormalities in a blood vessel leading to or within the brain
• Cancerous or noncancerous tumors
• Obstruction of cerebrospinal fluid flow
• Sinus infection
• Structural abnormalities in the head, neck or spine

You may be at greater risk of exercise headaches if you:

• Exercise in hot weather
• Exercise at high altitude
• Have a personal or family history of migraine

Exercise headaches tend to occur more often when the weather is hot and humid, or if you're exercising at high altitudes. If you're prone to exercise headaches, you may want to avoid exercising in these conditions.

Some people experience exercise headaches only during the performance of certain activities, so they may prevent their headaches by avoiding these activities. A warm-up prior to strenuous exercise also can help prevent exercise headaches.

Your doctor will likely recommend an imaging test, especially if:

• Your headaches last more than a few hours
• Your headaches strike suddenly, like a thunderclap
• You're older than age 40
• You have other signs and symptoms, such as nausea, vomiting or vision disturbances

In these cases, different types of imaging tests can help your doctor verify that you have the harmless variety of exercise headache, rather than the type caused by a structural or vascular abnormality.

• Magnetic resonance imaging (MRI). This test uses a magnetic field and radio waves to create cross-sectional images of the structures within your brain.
• Magnetic resonance angiography (MRA) and computerized tomography (CT) angiography. These tests visualize the blood vessels leading to and inside your brain.
• CT scan. A CT scan uses X-rays to generate a cross-sectional image of your brain. This test can show fresh or recent bleeding into or around the brain and is often used if your headache occurred less than 48 hours beforehand.

Sometimes a spinal tap (lumbar puncture) is needed as well, especially if the headache started abruptly and very recently and brain imaging appears normal.

If no underlying structural or vascular problem is causing your exercise headaches, your doctor may recommend medications to take regularly to help prevent the headaches.

• Indomethacin (Indocin, Tivorbex), an anti-inflammatory drug, is commonly prescribed.
• Propranolol (Inderal, Innopran XL), a blood pressure medication, also is used to prevent exercise headaches.

Other therapies, including naproxen (Naprosyn), phenelzine (Nardil) and ergonovine, have been reported to be effective in some people.

If your exercise headaches are predictable, you may be able to take a medication an hour or two before a scheduled event, such as a tennis match or a hike at high altitude. If your exercise headaches are frequent or unpredictable, you might need to take the preventive medicine every day.

You're likely to start by seeing your family doctor or a general practitioner. In some cases, you may be referred to a neurologist. It's good to be prepared for your appointment. Here's some information to help you get ready for your appointment, and to know what to expect from your doctor.

What you can do

• Be aware of any pre-appointment restrictions. When you make the appointment, ask if there's anything you need to do in advance, such as restricting your diet.
• Write down any symptoms you're experiencing, including any that may seem unrelated to the reason for which you scheduled the appointment.
• Write down key personal information, including past illnesses and operations, major stresses or recent life changes, and any medical problems that run in your family.
• Make a list of all medications, vitamins and supplements you take.
• Take a family member or friend along, if possible. Someone who accompanies you may remember something you missed or forgot.
• Write down questions to ask your doctor.

Preparing a list of questions will help you make the most of your time with your doctor. For exercise headaches, some basic questions to ask your doctor include:

• What's causing my symptoms or condition?
• Are there other possible causes for my symptoms or condition?
• What tests do I need?
• Is my condition likely temporary or chronic?
• What is the best course of action?
• What are the alternatives to the approach you're suggesting?
• I have other health conditions. How can I best manage them together?
• Are there any restrictions I need to follow?
• Should I see a specialist?
• Is there a generic alternative to the medicine you're prescribing?
• Are there brochures or other printed material I can take home? What websites do you recommend?

Don't hesitate to ask any other questions that come up during your appointment.

What to expect from your doctor

Your doctor is likely to ask you a number of questions, such as:

• When did you begin experiencing exercise headaches?
• Have your exercise headaches been continuous or occasional?
• Have you had a similar problem in the past?
• Have you had other kinds of headaches? Describe them.
• Has anyone in your immediate family experienced migraines or exercise headaches?
• What, if anything, seems to help your headaches?
• What, if anything, makes your headaches worse?