2016 Olympics mark a milestone in gender equality: the highest rate of participation by female athletes, 45%.

The International Olympic Committee’s (IOC) charter includes gender equality as one of its core commitments. It has steadily increased the number of events featuring female competitors. This year women compete in Golf and Rugby for the first time.

The importance of expanding sports like Rugby to women cannot be overstated. Even though I participate in sports regularly, it did not occur to me that women could play Rugby. I consider myself a feminist. But like most of us, I have an unconscious bias about what women can do vs. men.  When I watched the Rugby match between France and Canada over the weekend, new ground was broken for me.

There will be no Women’s Rugby league sign-up in my future, but to girls watching this year’s Olympics, Rugby might become their sport of choice.

This is what happened with female wrestling. This year Adeline Gray will try to win the U.S. a gold medal in this sport. She is a three-time world champion and a strong advocate of gender equality in combat sports. She told Fortune magazine:

“We’re still developing role models in women’s Wrestling,” Gray says. “It’s easy for boys to just pick a mainstream sport that we associate with strength and power and think about a future in the NFL or the NBA. But with women’s sports, there’s still this challenge of what do you do with your goals beyond four years of college sports.”

To get girls involved in these sports early takes funding. With wrestling, Fortune reports, that fewer than 10 state high school associations have girls wrestling sanctioned as its own sport.

Gray and athletes like her draw attention to these inequalities which also manifest themselves in other realms e.g. sponsorship dollars, professional salaries. There is still a distinctly large pay gap between male and female athletes.  So it was not surprising that despite Zika concerns, not one U.S. female athlete declined to participate in the games this year (though 14 male golfers did). Women know they have to work harder.

Critics will say pay is just a function of performance. But the U.S. Women’s Soccer team put those claims to rest when they sued their employer, U.S. Soccer Federation, for pay discrimination. Despite winning Three World Cups (while their male counterparts never advanced beyond the semi-finals), the women earn $99,000 per year compared to $263,220 for the men.

The best sport to play if you are a woman and want equitable pay is Tennis. Prize money is the same for women and men at all four grand slam events. Two female tennis players made Forbe’s World’s 100 Highest Paid Athletes list this year: Maria Sharapova ($29.7 million) and Serena Williams ($24.6 million).

But Sharapova and Williams are the exceptions to the rule. Most female athletes at this year’s Olympics struggle to pay for the costs associated with the trip. These are not people who are making a lot of money. They do it for the love of the sport. I am grateful that they do.