People who are sedentary may have a higher risk of developing frequent headaches, the results of a large study suggest.

The findings, based on surveys of more the 68,000 adults residing in Norway, found that those who never exercised were 14 percent more likely than their more active counterparts to develop non-migraine headaches over an 11-year period.

Conversely, people who were already suffering from any form of frequent headache were at greater risk of being physically inactive.

The findings suggest that a lack of exercise may be a risk factor for developing non-migraine headaches — and that exercise is a challenge for people already suffering from any form of head pain.

It's not clear why a sedentary lifestyle might contribute to headaches, lead researcher Emma Varkey, of the Cephalea Headache Centre in Gothenburg, Sweden, told Reuters Health.

But the findings suggest that protection from headaches could potentially be another reason for people to stay active, Varkey and her colleagues report in the medical journal Cephalalgia.

The findings are based on two large surveys of Norwegian adults age 20 and older. One questioned 22,397 adults about their exercise habits and other health factors between 1984 and 1986, and then assessed headache symptoms in a follow- up questionnaire 11 years later.

The second survey involved 46,648 adults who were questioned about their current exercise levels and any headache symptoms.

The fact that headache sufferers were more likely to be inactive is concerning, given the health benefits of exercise, according to Varkey.

"The study indicates that people with headache might need help (or) advice to increase their level of activity," she noted.

There are, however, still questions about the types of exercise that are best for people with frequent headaches, according to Varkey.

Exercise usually does not worsen common, tension-type headaches, she noted, but for some migraine sufferers, vigorous activity can trigger episodes of head pain.

Varkey added her researcher group will soon publish a study looking at an exercise regimen designed to boost migraine patients' fitness without worsening their condition.