When it comes to luxe workout wear, Katie Warner Johnson and Caroline Gogolak’s e-commerce site Carbon38 is a one-stop shop. Not only do they stock an in-house brand, but they also offer lines like Adidas by Stella Mccartney, Repetto, and Alala. Amidst running their empire and keeping...

The gig: Former TV producer Sophia Rossi, 34, is chief executive of downtown Los Angeles-based HelloGiggles, an ad-supported destination online for news and entertainment aimed at girls and young women. Time Inc. bought the start-up for around $30 million in October, allowing for more than...