NEW YORK (AP) -- Serena Williams and Mia Hamm are helping Billie Jean King spread the word about keeping girls in sports in conjunction with the 40th anniversary of Title IX.
Williams, a 13-time Grand Slam champion, is featured in national magazine ads that show her as a young girl whacking a tennis ball and the words: "If I walked away then, I wouldn't be here now."
Hamm, the former U.S. soccer star, has tweeted about the Women's Sports Foundation's campaign to promote active and healthy lifestyles. Girls drop out of sports at twice the rate of boys by age 14, according to the WSF.
The foundation that King founded wants to keep girls in the game longer through its youth programs, offset messages focusing on looks rather than abilities and help them become successful leaders.
If girls are involved in sports or physical activity by age 10, they're much more likely to be active at 25, King said. That can help fight obesity, which the Center for Disease Control reports has more than tripled in the past 30 years among ages 6-19.
Title IX passed on June 23, 1972, and opened doors for girls and women by banning sex discrimination in all educational programs - including sports - that receive federal funds.
That marked a banner year for the 28-year-old King, who won Grand Slam titles at Wimbledon, the U.S. Open and French Open to earn the cover of Sports Illustrated as "Sportswoman of the Year."
King spoke this week at a Senate hearing on Title IX and recently discussed with The Associated Press the importance of the law and the pivotal role her parents played in her sporting career.
Where have you seen the most progress from Title IX in the last 40 years?
King: "Probably just the participation level from 1 out of 27 girls in high school to 1 out of 2.5. You see how it's helped them go on to be great in business or just adapt better. I just love what it does for girls and for boys. It's funny, it's a big deal when a girl has these attributes, but it's kind of a given when you're a guy. It's all the same stuff that my brother (former pro baseball player Randy Moffitt) learned. It's a culture."
What role do parents play in sports?
King: "Parents are huge. Parents should get their kids into exercise of some sort, or go take a walk with them anyway. Get them in sports, if possible. I think a lot of time the father is the one that get the girls into sports, but now that we've got a few generations of Title IX babies, I think they definitely play a big part, too."
How did your father, the late Bill Moffitt, influence you?
King: "He'd play catch with me all day because he was home every other day as a firefighter in my young years. He would throw the ball so I could hit it. He'd ... time me when I ran from Molly's tree to our tree.
"When I was about 5, the boys wouldn't let me play. He says, `Everybody come over here, if you don't let Billie play, no one's playing. So let her play, she's very good, she can hold her own with you guys.' And we're just tiny. I was so embarrassed, but then I was so proud at the same time."
What lessons came from mother Betty Moffitt, who turned 90 this month?
King: "She gave us balance. It wasn't just sports, which was great. She was a jock herself, but didn't talk about it. She deferred to my dad a lot then, you know that generation. She was a good athlete, she was a good swimmer."