On the 8th floor of a building in New York's Garment District, Ms Denise Lee, 33, the owner of fitness line Alala, sits at her desk on a call with a supplier.
She smiles, waves and gestures apologetically that she is just about to wrap up. The room is filled with boxes and racks of fitness attire.
"Welcome to Alala," said Ms Lee, dressed in a cobalt-blue top from the Fall 2014 collection, after finishing the call. It has obviously been a busy day - like most days since she started her firm at the end of 2012.
Ms Lee, who has spent 14 years in the US, has always worked in the fashion industry, first at the marketing department of Armani Exchange, then as a business associate at Burch Creative Capital, whose chief executive Chris Burch is the former husband of fashion designer Tory Burch. But she always wanted to start her own business.
The opportunity presented itself while she was training for her first triathlon in 2012.
"Triathlons always interested me and I told myself I was going to do it before I turned 30," she said.
She trained five to six days a week for six months, and was constantly looking for new workout outfits that suited her but "nothing had the mix of style and function" that she wanted. So after the triathlon, she decided to take the plunge, quitting her job at Burch at the end of 2012.
About seven months later in July, she showed a full line of active wear to retailers. Her line was picked up by retailer Bloomingdales and popular New York fitness club Equinox, and hit the stores in 2014.
"Bloomingdales had a whole window of our stuff. It was great to see your dream and vision take shape," said Ms Lee, who is married and lives in New York.
A-list celebrities such as Ellie Goulding, Reese Witherspoon and Naomi Watts have been photographed in Alala outfits.
"Actually, Reese was wearing this design," said Ms Lee, pointing to her cobalt-blue top.
The firm is a small three-man team - there is also a designer and a brand coordinator - but Ms Lee revels in the idea that her brand is taking on bigger, more established sports names.
"It has become a really competitive market, but I think we entered it at the right time," said Ms Lee, who added that sales have doubled from last year. The company will soon be looking for investors to "turbo-charge the growth".
Asked if she would ever go back to working for someone else, Ms Lee paused before saying: "I think it would be very hard.
"I enjoy seeing all the parts of the business coming together... I don't think I would have that sort of access in a regular job."