Often called "Gotys" - Getting Older, Thinking Younger, the period is when individuals are go-getting, monetarily more secure and less worked out.
The study found that one in six over-50s turn to social networking websites and internet chatrooms.
Even after paying mortgages and raising kids, majority are still enjoying robust good health into their 60s and beyond.
However, the research, which is a part of the Government's "Generation Xperience" campaign to celebrate ageing, also reveals age discrimination cases, where many have been ejected from the workplace in their 50s and 60s.
The number is likely to exceed 1,000 per month by 2008.
Richard Linskell, the secretary of the Employment Lawyers Association and a partner at London firm Dawsons, predicted that age discrimination would turn out to be one of the most popular forms of claim.
The Government's research also found that over-50s felt more "inspired" than "retired".
The presentover-50s eat more healthily and have improved prospects in older stages of life than their parents did.
Almost one in three over-65s have more aims than they did in their younger days.
Close to 75 pct over-50s say they are happier now than ever before and around 80 pct say they have better prospects for later life than their parents did.
For only 5 pct, life after retirement meant boredom.
As regarding to spending later years, personal goals include more travel (82 per cent), acquiring computer skills (60 per cent), picking up a new activity such as painting or yoga (61 per cent) and getting back to school (43 per cent).
In financial terms, 60 per cent of over-50s feel they are better off.
"A wise older woman once said that she didn't mind being regarded as being over the hill because it's only once you're over the hill that you pick up speed," the Telegraph quoted Linda Kelsey, the author of Fifty is Not A Four-Letter Word, as saying.
"UK Older People's Day today is a chance to celebrate the contribution that 20?million people over 50 make to the UK and to tackle outdated stereotypes of what it means to be 'old'," Mike O'Brien, the pensions minister said.