A study assessing the impact of physical inactivity on national economies has suggested that if all adults aged 18-64 walked just 15 minutes more a day, the world economy would grow by an estimated $100bn a year until 2050.

The figure comes from a global study published by non-profit research institute RAND Europe and insurance giant Vitality.

It shows that if people who are currently physically inactive were to reach the World Health Organization’s recommended levels of exercise, employees would gain up to five additional days of productive time each year. This would result in the global economy to grow by an estimated US$220bn every year.

The increase in activity levels would also lead in life expectancy to increase by at least 2.5 years, on average, for a person aged 40 years.

In addition to getting inactive people active, if currently active people increased their physical activity levels by 20 per cent, the global economy could grow by in excess of US$360bn every year; equivalent to the size of Singapore’s economy.

Economic gains for the US economy would add US$95bn (£73bn) a year to the economy until 2050, and US$11bn (£8.5bn) a year for the UK economy.

“This ground-breaking study provides proof of the relationship between exercise, productivity, mortality and economic growth," said Adrian Gore, CEO of Discovery Group, which owns Vitality.

"It strengthens our resolve to continue to encourage people to move more and become part of a global health movement."

For the study, RAND Europe used a dynamic, multi-country macro-economic model to assess the impact of physical inactivity on national economies on a consistent basis, allowing for an aggregation of the effect to the global economy.

The study synthesises the existing evidence on physical activity and mortality risk by taking study design and publication bias into account.

“This is the first time that a multi-country macroeconomic model has been applied to the area of physical activity, facilitating a detailed assessment of the current and future implications of insufficient physical activity," Hans Pung, president of RAND Europe added.

“The study points to a significant relationship between inactivity and productivity loss, driven largely by ill-health related presenteeism. We hope that these insights will support policy makers and employers with new perspectives on how to enhance the productivity of their populations.”

Commenting on the study, ukactive CEO Huw Edwards said: “The study reinforces the message that physical activity is good for our health, community and economy.

“A relatively small increase in physical activity of an extra 15 minutes a day could extend life expectancy by two-and-a-half years, reduce sick leave by five days and adds an extra £8.5bn to the UK economy.

“It is clear that physical activity has a crucial role to play in improving the health, happiness and productivity of the UK, so we urge Government to do more to support people to lead a more active lifestyle.

“This report shows a new and welcome perspective on the why and the what. It is great to see health insurers such as Vitality Health and AXA PPP Healthcare continue to lead the way but it is critical that the physical activity sector continues to support employers, government and communities on the how.

“ukactive’s Research Institute has committed to undertaking the most comprehensive consultation to date on the role of physical activity in the workplace.

“This consultation will present back to us, the business community and the government, recommendations that will redesign how we work, and the support needed for businesses of all sizes to encourage physical activity.

“Through this work we can support the behaviour changes that this report indicates are vital.

“Together we can build a healthier, happier and more prosperous nation by getting everyone in society more active.”

To find out more about the RAND/Vitality study,

click here.