Javaid Nauman and colleagues from the Norwegian Univeristy of Science and Technology in Trondheim examined data from 25,089 healthy women whose cardiovascular health was assessed for an average of 18 years.

During the study, results of which have been published in the Journal of Epidemiology and Community Health, 1,814 women died as a result of cardiovascular causes.

For each increment of 10 heart beats per minute, women's risk of death from ischaemic heart disease was increased by 18%. Men's risk was only increased by 10%.

In women, but not men, the risk associated with resting heart rate was attenuated in those reporting high levels of physical activity. This suggests that increasing physical activity levels can reduce the risk associated with high resting heart rates, the researchers said.

But they added that the effect of physical activity does not completely account for the increased risk of death from ischaemic heart disease found in women with high resting heart rates.