Athleta is designed not for the working woman, but for the work-out woman. You can shop by sport and intensity - from snowboarding to tennis and golf. They offer sizes in talls, petites and plus.
And my favorite part? The have swimsuits specially designed for C-DD cups!
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They offer every item needed - swim, tops, shoes, sunglasses, jackets and so on... Check it out at athleta.gap.com.