Nike today revealed that 22 million running miles have been logged on its Nike+ website.

The miles covered by iPod nano-wielding, Nike+ footwear-wearing sporty types is the equivalent of completing more than 800,000 New York City marathons and burning off the calories of more than 5 million slices of pizza, the company points out.

Launched last year in partnership with Apple, Nike+ lets your iPod nano talk to Nike+ enabled running shoes through the wireless Nike + iPod Sport Kit. Data on time, distance, calories burned and pace is stored on your nano and is easily downloaded through iTunes to

Nike also promised new features will be introduced this summer. Taking a leaf from social networking sites, these new features will offer runners new ways to challenge each other and participate in "virtual" marathons.

Trevor Edwards, Nike's vice president of global brand and category management, said: "Nike+ started as a simple idea and has quickly become the world's largest networking place for runners."

New features to will include a challenge feature that provides users with more options and enhanced customization tools. Users can choose their own challenge theme, set their own rules, and select the number of participants and team names.