The Nike+iPod Sport Kit, which will be available in two months at $29, has already won an endorsement from Tour de France champion Lance Armstrong, who plans to run his first New York marathon later this year.
"It will take working out to a whole other level," said Armstrong, who appeared at the companies' news conference in New York City.
The co-branded kit comes with a sensor that fits inside compatible Nike footwear — sold separately — and a wireless receiver that attaches to the iPod.