MONDAY, Oct. 8 (HealthDay News) -- Fast walking and jogging every day can cut your risk of heart disease and stroke by as much as 50 percent, but an hour's walk every day does not make a difference, according to a new Danish study.

The researchers said their findings suggest that exercise intensity rather than duration is what matters in protecting against metabolic syndrome, which refers to a combination of factors -- such as high blood pressure, elevated blood sugar levels, abnormal blood fat levels and abdominal obesity -- that increase the risk of heart disease, diabetes and stroke.

The study was published Oct. 8 in the online journal BMJ Open.

Researchers Eva Prescott and colleagues at Bispebjerg University Hospital, in Copenhagen, looked at more than 10,000 Danish adults, aged 21 to 98, who were first assessed between 1991 and 1994 and then followed for up to 10 years. At the initial assessment, about 20 percent of women and 27 percent of men had metabolic syndrome.

At the study's beginning, those who were least active were most likely to have the syndrome. Nearly one-third of inactive women and about 37 percent of inactive men had metabolic syndrome, compared with 10 percent of physically active women and about 14 percent of physically active men, according to a journal news release.

By the end of the study period, metabolic syndrome had developed in about 15 percent of the people who didn't have the syndrome at the start of the study. The syndrome developed in about 19 percent of inactive people and 12 percent of those who were very physically active.

Further investigation showed that it was not only the amount of exercise, but also the intensity that helped reduce the risk of metabolic syndrome. Fast walking cut the risk by 50 percent and jogging cut the risk by 40 percent, while going for an hour-long walk each day did not make any difference.

More information

The U.S. National Heart, Lung, and Blood Institute has more about metabolic syndrome.