The Dow Jones reached record highs when it crossed the 23,000 mark for the first time in its history, Tuesday.

Following 8 years of steady stock market growth, a study by Wells Fargo says 65 percent of working Americans believe the stock market is the best place to grow retirement savings compared to 45 percent a year ago.

Some experts, like Jim Heafner of Heafner Financial, say workers shouldn't over invest in stocks in the last 10 years leading into retirement.

"So we're going to have to have some way to be able to minimize the impact of a downturn because it could happen at anytime," he says.

When the market is up, like now, experts recommend re-evaluating your asset allocation.