While exercise can help prevent headaches and migraines, in some instances—typically due to intense exertion and increased blood pressure—it can cause them. Elizabeth Barchi, MD, a sports medicine specialist at the Center for Women’s Sports Health and clinical assistant professor in the Department of Orthopedic Surgery at NYU Langone, breaks down the various causes for POPSUGAR.

Weightlifters may get a headache from a common technique of holding their breath while pushing the weight. An exertional headache, on the other hand, is caused by increased blood pressure due to intense bouts of exercise. Endurance athletes may get headaches from exercising in bright light or extreme heat, or because of dehydration.

If you start to develop a headache during a workout, Dr. Barchi recommends resting and stretching before starting the exercise again. “Go back at 50 percent of the intensity, and then try to go from there,” she says. “But if the headache’s not getting better, even with 10 minutes of stretching, that’s when I’d say call it a day.”

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