Michael Phelps pitches Under Armour T-shirts

Fri, Mar 11
Michael PhelpsCourtesy of Under ArmourNormally shirtless, Michael Phelps shoots a commercial for Under Armour's new line of T-shirts.

Michael Phelps competes in the water. So why was he shooting a commercial the other day for Under Armour's new line of Charged Cotton T-shirts?

"Actually, a lot of my training takes place out of the pool," said Phelps during a break on the set. "Whether it's working out in the weight room, or running, or even boxing -- it's not all in the water."

Fair enough. But here's a tougher question: For years now Under Armour founder Kevin Plank has been saying, "Cotton is the enemy!" to anyone who'll listen, so why is Under Armour now getting into cotton T-shirts?

The answer apparently came during a recent Under Armour earnings call, when Plank explained the situation like so:

"You talk to an 18-year-old kid and he's got 30 T-shirts in his drawer, 26 of which are cotton, four of which are technical performance. Three of the four of which are Under Armour. And we've been trying to get that fourth T-shirt to convert to Under Armour as well. And then we looked at the opportunity and said, 'What about those other 26 shirts?'"

Translation: If you can't beat 'em -- well, you know.

So what exactly is Charged Cotton anyway? It's a basic cotton tee, but with 5 percent elastane (a fancy-sounding synonym for spandex) to provide a bit of stretch, and all the usual moisture-wicking, fast-drying features that every new athletic shirt has nowadays.

There's no denying that it's softer and nicer to the touch than the usual Under Armour material, which is what Phelps likes about it. "It's so much more comfortable," he said.

So comfortable that he'd wear it in the pool? "Well, that might be pushing it a bit," he said.

Translation: Cotton is still the enemy in certain situations. At least until that moisture-wicking technology take a few quantum leaps.