People who are active are up to 47 per cent less likely to die from a heart attack (myocardial infarction) than someone who doesn't exercise, say researchers from the University of Copenhagen.
They aren't sure why this is, but they reckon that people who exercise have better blood flow to the heart even when there is an attack.
The researchers tracked the health of 14,223 participants in the Copenhagen City Heart Study; none of the participants had suffered a heart attack or stroke when they registered for the study between 1976 and 1978, and their levels of exercise were also noted.
During the trial, which ended in 2013, 1,664 of the participants suffered a heart attack, and 425 of them died immediately. Those who exercised moderately were 32 per cent more likely to survive the attack, and those who exercised the most were 47 per cent more likely to live.