More than 20m UK adults are increasing their risk of heart disease and costing the health service as much as £1.2bn (US$1.5bn, €1.4bn) each year because of physical inactivity, a British Heart Foundation (BHF) report has revealed.

The Physical Inactivity and Sedentary Behaviour Report found that 39 per cent of adults are failing to meet government guidelines for physical activity.

The 10-page report revealed:

- around 11.8m women across the UK are insufficiently active, compared to around 8.3m men- women are 36 per cent more likely to be classified physically inactive then men

- in England, 39 per cent of adults - around 16.8m – are physically inactive- in Northern Ireland, 46 per cent of the adult population – around 650,000 people – are inactive

- in Scotland, 37 per cent of adults – around 1.6m people – are physically inactive- in Wales, 42 per cent of the adult population – over 1m people – are physically inactive.

In England, the North West is the worst region as almost half of the adult population – 2.7m adults – are insufficiently active.

According to the report, around 60 per cent of adults are unaware of the government’s physical activity guidelines. The government recommends that adults take part in at least 150 minutes of moderate intensity physical activity a week and strength activities on at least two days a week. It is also recommended that adults minimise their levels of sedentary behaviour.

Evidence is growing that also shows a sedentary lifestyle, regardless of how physically active you are, is associated with poor health. The BHF estimates that the average man in the UK spends a fifth of his lifetime sitting – the equivalent of 78 days each year. For women this is around 74 days a year.

The report shows that physical inactivity is high among people who have gone on to suffer a cardiac event. Three quarters of people in England (76 per cent), when referred for cardiac rehabilitation after suffering a heart attack or undergoing heart surgery, are considered physically inactive. In some areas of the UK this figure is as high as 97 per cent of patients.

The BHF is launching its MyMarathon challenge, which urges people to kickstart a more active lifestyle to help improve their heart health. The challenge encourages people of all fitness levels to run 26.2 miles in their own time over a month, from as little as a mile a day.

Dr Mike Knapton, associate medical director at the BHF, said: “Physical inactivity is one of the most significant global health crises of the moment. Levels of physical inactivity and sedentary behaviour in the UK remain stubbornly high, and combined these two risk factors present a substantial threat to our cardiovascular health and risk of early death.

“Making physical activity easier and more accessible for all is of paramount importance if we are to reduce the burden of inactivity-related ill health. Our MyMarathon challenge is an ideal way for people of all fitness levels to increase their physical activity and improve their heart health. Every pound raised will help fund vital research in the fight against heart disease.”