Swift walking, jogging and other similar exercise each day can halve the risk of heart disease and strokes, but a simple hour-long stroll can make barely any difference at all, according to research in the online BMJ Open journal.
The experts behind the study say this suggests the intensity of exercise is more important than the duration in reducing the effects of metabolic syndrome - a series of problems such as midriff bulge, high blood pressure, insulin resistance, higher than average levels of blood glucose and unusual blood fat levels.
Experts believe genes, diet, and low exercise are related to the syndrome, which can lead to inflammation and blood thickening.
The research comes from a study of more than 10,000 Danish adults aged 21 to 98, started in 1991-94 and monitored for as long as 10 years.
All 10,000 were asked about how much exercise they undertook, and it was then categorised by intensity and duration.
The research found that it was both the amount and the intensity of exercise that helped to reduce the chances of metabolic syndrome.
The results suggested that swift walking speeds could reduce the risk by 50% and jogging could reduce the risk by 40%, but an hour’s gentle walk had little to no effect at all.
“Our results confirm the role of physical activity in reducing [metabolic syndrome] risk and suggest that intensity rather than volume of physical activity is important,” said the researchers.