Summer means baseball, and baseball means thongs.

Well, it did for one summer at least, a few years back, when then-New York Yankee Jason Giambi admitted that he sometimes wore a lucky thong (tiger print, gold lamé) when he hit a slump. He added that he lent it to his teammates when they needed a lift, too. Apparently, nothing excites athletes like women's underwear ... even on themselves.

Now it turns out my home team heroes weren't quite as batty as they sounded at the time. A new study by researchers at the University of Cologne reported in the current issue of Psychological Science finds that a good luck charm can actually improve a person's performance.

This is not because the charms possess real magical power. (Though who knows?) The researchers — psychologists — hypothesize that a charm boosts its owner's confidence, which in turn boosts his (or her) performance. Could that be true?

Lead researcher Lysann Damisch noticed — as have we all — that athletes seem to be a particularly superstitious bunch. Michael Jordan wore his old blue University of North Carolina shorts underneath his NBA shorts for good luck. Serena Williams once admitted wearing the same pair of socks throughout an entire tournament. (Maybe she won by asphyxiating her opponents.) Tiger Woods supposedly wears a red shirt on the Sundays that he plays professionally. (And just think how much luckier he'd be today if he never took his clothing off.)

Anyway, Damisch knew that prior research on superstitions focused mainly on when and why people indulge in them. They generally do this in times of stress, when they have to perform and are worried that they might not make the grade — sometimes literally. Like athletes, students are a superstitious bunch. The lucky charm or superstitious behavior ("If I don't step on the foul line, I'm good to go!") gives the fretter a feeling of being in control. It's a stress reliever. But Damisch wondered whether maybe it isn't more than that.

Can a lucky rabbit's foot — or stinky sock — actually improve performance?

To find out, she and her colleagues Barbara Stoberock and Thomas Mussweiler conducted several experiments. In one, they asked students to take part in a test and bring a lucky charm with them.

The researchers then whisked away the charms — stuffed animals, rings, stones — ostensibly to photograph them. They gave the charms back to half the students and then had them all perform a memory test. The students in possession of their charms did better than the ones without!

In another experiment, the researchers asked students to play a putting game. Half of them were told, "Here is your ball. So far, it has turned out to be lucky!" The other half were just told, "Here's your ball." The ones with the "lucky" ball did better. And in yet another test, half the students were told the German equivalent of "I'll keep my fingers crossed for you!" And that half did better on a dexterity test.

All of which seems to suggest that when people do the silliest, most superstitious things, be that rubbing the batboy's head or wearing a gold lamé thong to an all-star game, they may actually be indulging in high-powered psychological enhancement.

Or maybe they just like wearing ladies underwear. Beats steroids!

Lenore Skenazy is the author of "Who's the Blonde That Married What's-His-Name? The Ultimate Tip-of-the-Tongue Test of Everything You Know You Know — But Can't Remember Right Now" and "Free-Range Kids: How to Raise Safe, Self-Reliant Children (Without Going Nuts with Worry)." To find out more about Lenore Skenazy (lskenazy@yahoo.com) and read features by other Creators Syndicate writers and cartoonists, visit the Creators Syndicate Web page at www.creators.com.