We can't be bothered to walk up a few flights of stairs, balk at the idea of running to catch a bus and would rather snooze than have sex with our partners, according to a report published today.

Despite a huge government push to encourage healthy living, Britons are lazier than ever, concludes the study conducted by Nuffield Health, a not for profit health organisation.

One in six people would rather watch a TV programme they didn't like than leave the sofa to change the channel if their remote control was broken. A third (36%) of the 2,000 adults surveyed for the study said they would not run to catch a bus and more than half (59%) would not walk up two flights of stairs to reach their office, choosing instead to take the lift.

More than half of dog owners (52%) did not walk their dogs, and two-thirds (64%) of parents admit to always being too tired to play with their children.

The laziness epidemic appears to have spread to the bedroom, with almost three-quarters (73%) of couples saying they regularly do not have enough energy at the end of the day to have sex, with more than half (58%) blaming a lack of fitness.

Glasgow is the laziest city in the UK, with 75% of people admitting they don't get enough exercise, followed by Birmingham and Southampton in joint second place with 67%; Bristol is in third with 64%, and London in fourth. Bristol, Leeds, Newcastle, Norwich, Manchester and Cardiff make up the rest of the top 10.

It appears Britons are paying little heed to the government's Change4Life campaign – which encourages people to "eat well, move more, live longer" – but may be motivated by more superficial concerns. Almost a third (28%) of respondents would be prepared to exercise more if they felt it would make them more attractive.

A whole generation is in danger of becoming too unfit to perform rudimentary tasks, said Dr Sarah Dauncey, medical director of Nuffield Health.

"Ready meals, remote controls and even internet shopping are all contributing to a dangerously lazy and idle Britain. The nation has fallen into a vicious circle of laziness that we must stop," she said.