A generation of 'Wearies' – Working, Entrepreneurial and Active Retirees – could be forced to continue working into their seventies and beyond due to hardships caused by the looming pensions crisis.

Effectively ruled out of employment by age, they will set up their own businesses, according to the study for Friends Life by think tank Future Foundation. Many of tomorrow's OAPs will look to supplement their retirement savings by becoming self-employed in their later years.

Many are likely to supplement their income buying and selling goods on websites like eBay, while others will turn their front rooms into offices or cottage industry workshops or a nursery. Those with manual skills might set up gardening or home help businesses to make money helping neighbours, academics predicted.

Martin Palmer, head of corporate benefits marketing at Friends Life, said:

"We're expecting the traditional image of the pensioner with slippers and rocking chair to change completely.

"Many will not have saved adequately for a secure retirement and, with years of fiscal austerity taking their toll, by 2020 many people in their seventies simply will not be able to afford to give up working.

"Necessity is the mother of invention and Wearies will be among the most innovative and entrepreneurial contributors to the UK economy, despite their senior years."

People from across Britain were asked about their attitude to working in retirement as part of the study, entitled "Pensions: Crisis and Reforms".

Over half (51%) of those who are already retired said they would be prepared to do part-time work to boost their pensions. But the figure rises to three-quarters (75%) among those who are yet to retire.