LONDON – STELLA McCartney’s sportswear franchise is saddling up to take on the cycling world. The British designer may be better known for her tops and dresses, but her active-wear ‘adidas by Stella McCartney’ concept has been going strong since 2005. In addition to her pre-existing ranges devoted to yoga, tennis, golf and swim, McCartney is now working to keep cyclists, runners and triathletes looking sharp on the track and in the pool. The sports apparel on dis