By Sarah Weld

I stand on the sidelines watching my soccer team. I can hear my girls breathing hard as they sprint past, see their fierce faces. One of them collides with a player from the other team, fights to hang on to the ball, then takes off down the field.

For 70 minutes they run, dribble, fall down, tackle, shout, and (hopefully) score. And when they come off they are sweaty, eyes bright. And despite the outer trappings of being 12 years old -- they sport painted fingernails, listen to boy bands, flip their hair, and wear skinny jeans -- when they play soccer, they are tough, unrelenting, and commanding. All the adolescent nuttiness falls away and they are simply -- and beautifully -- soccer players. They are girl athletes, and above all, just athletes.

When I was 12 (circa 1977) my mother taught me how to throw and catch a lacrosse ball in our backyard. She had learned in her Pennsylvania high school, where the girls taught the boys how to play. But in college she played no sports, because there were scant few athletic opportunities for women in the late 1950s.

Then in 1972 came Title IX, which forbids any school receiving federal funding to discriminate on the basis of gender. As a result, girls crowded fields and gyms for a chance at something other than spectating -- 1,000 percent more high school girls do sports now than in 1972. Five hundred percent more college women play varsity athletics.

In addition to physical fitness and discipline, the benefits of athletics are vast. Girls who play sports respect strong muscles; model-thin legs don’t help you jump high. Athletic girls make healthier choices about drugs and getting pregnant. If you smoke, you can’t run. If you’re busy with basketball or track and homework, there is little time to lose your way.

Arriving in high school in 1979, I was lucky to attend a school that offered many sports -- for me, soccer, cross-country skiing, and lacrosse. I went on to play two sports in college, and my time on the field saved my equilibrium throughout.

I still bike and run, but, sidelined due to injuries, I sorely miss my time on the soccer field. My role is now permanently as coach, cheering these young women on. I teach them how to be leaders and teammates, and how to deal with an off day. I remind them that cooperation isn’t an exclusive choice, that sometimes it takes cutthroat competition to win games, that if you have a shot you should take it.

My job is to teach them what that feels like, so they can take it with them wherever they go, whether it be a board meeting, a laboratory, Carnegie Hall, or the Oval Office.

Speak out. Run fast. Fight back. Work in pairs, and as a team. Know when to support, and when to fly alone toward the goal, then smack the ball hard at its sweetest spot, and watch it fall like a slingshot just under the crossbar, slightly shaking the white ropes of the net as it drops inside. Then run shouting, arms high, into the crush of your teammates rushing to embrace you.

(Sarah Weld is the co-editor of The East Bay Monthly, where this article first appeared. Weld, who coaches youth soccer for East Bay United/Bay Oaks in Oakland, Calif., played soccer and lacrosse at Harvard.)