The problem is a common one in the arena of personal finance: You're approaching the age at which you've planned to retire, but you don't have enough money saved. What do you do?

The solution is a common one, too: Work longer. You'll hear it from financial planners — and from Washington as well. A White House commission investigating ways to keep Social Security from running out of money is considering raising the age when full retirement benefits kick in; currently 66, the full retirement age is slated to rise to 67 by 2027. Moving the retirement age up to 70 is in the realm of possibility.

But the "work longer" solution sounds awfully blithe to many Americans, because it assumes that you can work longer. And let's face it: For many people — from a celebrity superathlete such as Michael Jordan to any working stiff — that's just not realistic.

As John Leland points out in The New York Times today, if you have a job that requires physical activity more strenuous than sitting at a computer, your ability to do that job can be drastically different at age 69 than it is when you're 62. According to the Center for Economic and Policy Research, about 45% of workers age 58 and older are employed in physically demanding jobs or jobs with difficult working conditions. That's more than 8.5 million people.

Even if you're a desk jockey, you can't always work into your 60s or 70s. Sure, there are age discrimination laws on the books. But ask any fiftysomething who works in an industry where staying on top of trends is key — fashion, advertising and music, for example — and you'll hear how hard it is to get and keep a good job in that field after you hit a certain age.

What about training for a new job? Well, sure. But such training costs money, and with unemployment still well above 9%, a job at the end — especially a job that pays what you once made — isn't a sure thing.

But enough with the depressing news. Instead of wringing our hands, we should be saying to ourselves, "OK, this is the reality these days. What's the best way to manage it?"

For starters, I'd propose that people tailor their retirement planning not to their age — the default way of doing it — but to the number of years they're likely to make good money in their chosen field. More and more, people in certain industries need to think a little more like professional athletes. They make their money early and — if they're smart — save as much of it as they can. That way, when their careers end, they can take a job that pays less or do consulting work part time. Or even, just maybe, retire early.

Are you changing your own retirement planning to deal with the new realities? Please share by posting to comments.

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