(AP) For Billie Jean King, 70 is the new 40.
The tennis great, who turns 70 in November, has been celebrating the 40th anniversary of equal prize money at the U.S. Open, the formation of the WTA tour and her victory against Bobby Riggs in the "Battle of the Sexes" match.
King was 29 when she accomplished those feats in 1973. On Tuesday night, PBS will highlight her career with the national premiere of "American Masters: Billie Jean King."
The series' first profile of a sports figure focuses on the professional tennis tour's start amid the women's movement and features interviews with Gloria Steinem, Chris Evert, King's doubles partner Rosie Casals and her brother Randy Moffitt, a former pitcher for the San Francisco Giants.
Thanks to King's efforts, Serena Williams earned a check for $2.6 million the same as Rafael Nadal for winning the U.S. Open.
Here's a five-part Q-and-A with King, who these days is giving tips to young tennis players Sloane Stephens and Victoria Duval:
Q: You received about two-thirds less in prize money for winning Wimbledon in 1968 compared with Rod Laver. What kind of leverage did it take to get equal prize money at the U.S. Open in 1973?
A: The U.S. Open was way ahead of its time, actually, compared to how long it took the other three majors to come around (Wimbledon last in 2007). We did it quietly, behind the scenes. There were two sponsors who said they would make it equal they would put in the money to make up the difference. I said, "Now we're talking, because now we're talking business."
Q: Why were sports an effective way to express what the women's movement was about in the 1970s, especially the tennis match you won against Riggs?
A: I talk about feminists, how they were all from the neck up in the '70s. This was not from the neck up, it was the whole body. It's very important for people to trust their bodies. It was the first time women started to think about all of themselves, instead of just their brains. It's really about their physicality. Sports are very different from other performing arts because you can't rehearse, you have an opponent and you sweat.
Q: You wanted the men's and women's tours to team up in the 1970s. Why do you believe the WTA managed to flourish and become a successful global enterprise that now offers $118 million in total prize money for 54 events in 33 countries?
A: I think because we had to and we showed that there is a market for women's sports. This wasn't really about me and the few of us, this was about the future generations. We had great early leadership.
Did I want the men and women together to have one voice? Absolutely. But the men rejected us and that's life and so you go to Plan B. Everybody pulled together eventually and we made it happen.
We also have a mentoring program, which I think is really important for the women. I do a power hour, two sessions every U.S. Open. They bring in a lot of the young players, our future top 10 or 20. We talk about the history, we connect. As rookies, they have to learn the history of the WTA. All of those things combined add up to the cohesiveness that we have as women athletes in the WTA.
Q: What are your thoughts on gay rights in Russia and a possible boycott ahead of the Sochi Olympics?
A: You have to ask the athletes and whatever they decide. I've talked to some of them and they're trying to figure out what's best. They believe in no discrimination at all, in anything, especially sexual orientation.
I'm not the athlete trying to go there and win a medal in the Winter Olympics. I can't walk in their shoes, exactly. I personally, as an athlete, would be very happy not to go to protest. But am I doing more good by going and being there or doing things with it or am I better off not to? That's always the challenge.
The LGBT community, it's the civil rights issue of the 21st century, at least the first half of it. We're at the tipping point.
Q: Could you have imagined the accomplishments in your life?
A: I knew as a youngster I wanted to be No. 1 in tennis. I knew by 12 my platform would be tennis, but my real life was going to be wrapped around equality and social justice. I felt like I had a tremendous sense of destiny.
As King points out in the documentary, "I know I'm very idealistic. I'm off the charts on it. But that's OK I think that's what keeps me going. I've been yelling and screaming that I've got one big thing left in me."