Sport England has published its latest Active Lives Adult Survey (ALAS), which shows that 27.7 million people – 61.8 per cent of the adult population in England – are physically active for more than 150 minutes a week.

Published today (22 March), the third edition of ALAS also reveals that efforts to lower the number of inactive adults have failed, as more than a quarter of the population – 25.7 per cent – remain inactive.

While activity levels across England have remained static, perhaps the most significant finding in the report is the suggestion that there is a shift away from traditional physical activities to more “modern” forms of exercise.

Swimming and cycling have suffered dramatic decreases in popularity, with almost 283,000 fewer people swimming regularly, and 93,000 fewer people cycling.

A striking feature of the data shows that they have been replaced by other activities.

There has been a huge increase in the number of people – a jump of 518,000 – doing interval training sessions, such as HIIT classes.

Figures show 20 per cent of people did their interval training sessions at home, and 75 per cent in a leisure centre or gym.

A significant proportion of the people doing interval sessions (47 per cent) are young people aged 16-34, which coincides with an increase in the number of HIIT classes available for free on YouTube.

Adventure sports has also enjoyed a boost in popularity, with 337,000 more people taking part in activities such as hill and mountain walking, rock climbing, abseiling, orienteering, or high ropes.

Other findings in the report include a stabilisation in the gap in activity levels between the higher and lower socio-economic groups – although people on lower incomes and disabled people are still much less likely to be active enough to benefit their health.

One of the few segments of society showing evidence of getting more active as a whole are older people, with the number of 55 to 74-year-olds meeting the 150 minutes threshold increasing by 1.3 per cent, to 58.3 per cent.

Announcing the report, Sport England CEO Jennie Price said: “While the overall activity levels of the nation are stable, what people are choosing to do is moving with the times.

“The popularity of HIIT shows the power of social media, and many older people are choosing to spend their leisure time in the great outdoors.

“Sport England has worked closely with the National Trust, the Forestry Commission and others to support more activity outdoors, and this remains a significant area of investment for us.

“The figures also show the huge importance of investing to tackle inactivity and the inequalities between different groups in society, which was highlighted in the Government’s strategy Sporting Future. It's why Sport England's 2017-21 strategy has, for the first time, allocated 25 per cent of its investment to tackling inactivity.

"This is a long-term task but it could not be more important."

ALAS was launched in 2015 to replace Sport England's Active People Survey and measures activity in its broadest sense – including activities such as walking, cycling for travel and dance – rather than just sport, to reflect the government's strategy Sporting Future: A New Strategy for an Active Nation.

A total of 198,911 people aged 16 years and over completed the second round of the survey between November 2016 and November 2017.

Commenting on the findings, Steven Ward, CEO of ukactive, said: “Despite progress in some areas, we continue to see vast inequalities in access to physical activity, fuelling the health crisis in Britain today.

“Physical inactivity is the UK’s silent killer and the only way we will defeat it is by encouraging more people to build physical activity into their daily lives.

“This mission requires a sustained approach that draws on the strengths of every local service and organisation, to reach all corners of society. We need to foster new partnerships, across the public and private sector, to fundamentally change the way people engage in physical activity.

“Thankfully, innovation is alive and well in our sector, from the ever-expanding range of HIIT and group classes available, to the tech start-ups joining our ActiveLab programme, bringing the best minds together in order to accelerate advanced solutions.

“Organisations, operators and suppliers are developing training and products to ensure exercise is made more accessible to disabled people, and our upcoming school summer camps will aim to bridge the health divide in struggling communities.”