Forget clunky strap-on heart-rate monitors. Adidas by Stella McCartney’s new performance bra includes a built-in miCoach device that tracks your cardio stats in real time. As seen on tennis champ Caroline Wozniacki, the high-tech racerback also features Adidas’s ClimateLite technology, which wicks moisture from the skin to the fabric surface for quick evaporation. Team GB or Team Get Off Your Butt; it’s your call.

+ Tennis Performance Bra $60

+ Adidas by Stella McCartney