How Sportswear Became Fashionable

Twenty-five million women currently train with Nike's two training apps, nike+running and nike+training. At any time of the day or night, says Trevor Edwards, the British-born president of Nike, you can log on to nike.com and observe a Babel of animated feeds (and, of course, purchase merchandise). "You'll find women discussing what they like and don't like about a product," says Edwards. "And also which forthcoming events they're taking part in."

This is a level of engagement that media organizations, fashion brands and governments—especially governments—would kill for.