Drop dead! Not if you ride a bike.

Physical activity such as riding a bike greatly reduces your risk of dropping dead from a heart attack, new research shows.

In a study of 28,000 people from across Europe, 18% died within 28 days of a heart attack, and of those 62% died instantly.

But if you engaged in moderate physical activity your risk of instant death from a heart attack was 33% lower, and if you engaged in high levels of physical activity your risk dropped 45 per cent.

And your risk of dying within 28 days of a heart attack was 36% lower (moderate activity) and 28% lower (highly active) compared to sedentary people.

The study by researchers in Copenhagen appears in the European Journal of Preventive Cardiology.

Heart disease is the leading cause of death globally and prevention is a major public health priority.

The beneficial impact of physical activity in stopping heart disease and sudden death on a population level is well documented.

This study focused on the effect of an active versus sedentary lifestyle on the immediate course of a heart attack – an area with little information.

Study author Dr. Kim Wadt Hansen of Bispebjerg Hospital, Copenhagen, Denmark said: “Almost 18% of patients with a heart attack died within 28 days, substantiating the severity of this condition.

"We found an immediate survival benefit of prior physical activity in the setting of a heart attack, a benefit which seemed preserved at 28 days.”

The authors said in the paper: “Our pooled analysis provides strong support for the recommendations on weekly physical activity in healthy adults stated in the 2016 European Guidelines on cardiovascular disease prevention in clinical practice; especially as we used cut-off values for physical activity comparable to those used in the guidelines.”

The guidelines recommend that healthy adults of all ages perform at least 150 minutes a week of moderate intensity or 75 minutes a week of vigorous intensity aerobic physical activity or an equivalent combination thereof.

Dr. Hansen said: “There are many ways to be physically active at little or no cost. Our study provides yet more evidence for the rewards of exercise.”

Participants were categorised according to their weekly level of leisure-time and physical activity as sedentary, low, moderate, or high.

The analyses were adjusted for age, sex, diabetes, blood pressure, family history of heart disease, smoking, body mass index, blood cholesterol, alcohol consumption, and socioeconomic status.

This article was made possible by the support of Bicycle Network's members who enable us to make bike riding better in Australia.