You may not recognize her name, but Misty Copeland is one of the fastest-rising stars in the American ballet scene. She dances as a soloist in the American Ballet Theatre and, as of last week, is joining the marketing roster of athletic apparel maker Under Armour (UAA). Specifically, Copeland will be featured in the company's "largest marketing campaign to-date for its Women's brand," according to an Under Armour release. 

With the fall of lululemon athletica (LULU -0.03%) last year, the market for women's athletic wear opened up wide. That allowed Under Armour and Nike (NKE 0.66%) to make bigger moves into the space, taking advantage of Lululemon's brand weakness. Adding Copeland to its marketing roster is just one of a series of moves aimed at making Under Armour the go-to brand for female athletes.

A lineup of champions
In addition to Copeland, Under Armour has signed deals with athletes including tennis star Sloane Stephens and skier Lindsey Vonn. The company hopes to grow its sales through tapping what has often been an overlooked demographic: female competitors and athletes.

The revenue and pay gap between men and women in sports is wide. WNBA players, for instance, cap out at $107,000 per year. According to ESPN's salary tracker, there are 542 NBA players who make more than that.

In part, the distinction is historic. Women's sports haven't been as popular as men's, and attendance at similar games is often heavily skewed toward the men's teams. The Chicago Bulls brought in 21,000 fans on an average home game night in 2012, while the WNBA's Chicago Sky hit a high of slightly more than 13,000 . However, the gap is shrinking; at last year's U.S. Open, the women's final recorded a higher TV rating than the men's final.

The goal for women's athletic sales
For fiscal 2013, Under Armour estimates that women's gear sales will bring in nearly $500 million in revenue. By fiscal 2016, the company wants to generate $960 million in that space. It's got a strong start, in terms of branding, with the strength of its Armour Bra line. In 2013, it parlayed that into strong sales across its whole studio platform, which competes with Lululemon.

Nike is following right along, drinking Lululemon's milkshake right in front of it. The company predicts that total revenue can top $36 billion by fiscal 2017, due in part to strong growth in its women's line. Both brands are chasing the underdeveloped market because of its huge potential.

Right now, Under Armour is taking a stronger marketing approach. The company is attempting to recreate the success it had with its men's line, targeting well-known athletes to market Under Armour as a performance line to other athletes. The Copeland agreement is another strong step in Under Armour's path to more revenue, and it's setting 2014 up to be a very interesting year.