NEW YORK (MainStreet) — If you're looking to put the finishing touches on your retirement plans, a study from MassMutual has a suggestion on timing: "Retirees who expressed the highest levels of satisfaction in retirement are also those who took concrete steps to put both their emotional and financial lives in order at least five years or more before retirement."

Unfortunately, only 31% of U.S. adults heading toward retirement "carefully research and plan every detail of their retirement plans," MassMutual says. And only 11% map out "every detail" of their retirement, while 36% admit to "winging it" with their financial strategy. (MassMutual points out that U.S. adults are three times more likely to wing their retirement than their vacation plans.)

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There is some good news for future retirees, who could use some at a time so many struggle to cobble together a decent retirement fund: A majority of retirees say they are happy in retirement and that pre-retirement anxieties about being bored or financially strapped are significantly overstated.

"Our research on retirees and pre-retirees tells us that retirement can be and should be an extraordinarily happy time in our lives as long as we start to strengthen our emotional bonds and exercise financial planning discipline well before we plan to retire," says Elaine Sarsynski, executive vice president at MassMutual Retirement Services. "The happiest retirees provide us with a roadmap for success, which is especially instructive for those who are close to embarking on the journey."

The study has more "lessons learned" from retirees on how they found happiness in retirement:

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  • Retirees who took steps to "build stronger connections" to their loved ones and "pursued new interests" were way more likely to enjoy their post-career years.
  • Retirees who laid out a careful plan for the financial side of retirement (such as calculating the best time to start collecting Social Security, and who accelerated retirement savings as they neared retirement) appeared "most satisfied."
  • The biggest good retirement surprises included having no time constraints, keeping busy and having enough money; bad surprises included suffering an illness or weak health and having unexpected cash problems.

— By Brian O'Connell for MainStreet