Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

What: Shares of Old Dominion Freight Line (Nasdaq: ODFL) sank as low as 13% in intraday trading Wednesday after the trucking company said it may raise up to $100 million of fresh capital through an "at the market" common stock offering.

So what: Old Dominion said it would use the proceeds to finance future capital expenditures and acquisitions, but investors are naturally concerned with the likely dilution that will result from the stock sale. So much so, in fact, that Old Dominion's shares are sliding on a day that it also reported an impressive analyst-topping, profit-doubling fourth quarter.

Now what: I'd keep my distance from Old Dominion for the time being. The shares are still up more than 65% over the past year, and today's stock sale announcement might be yet another sign of overvaluation. For my money, rivals FedEx (NYSE: FDX) and UPS (NYSE: UPS), whose stock prices aren't nearly as hot, offer far safer ways to play the industrial tailwinds we've been seeing.

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Fool contributor Brian Pacampara owns no position in any of the companies mentioned. FedEx is a Motley Fool Stock Advisor recommendation. The Fool owns shares of FedEx. Try any of our Foolish newsletter services free for 30 days.

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