Forty years ago, young women weren't supposed to do a lot of things. They weren't supposed to be smarter than young men. They weren't supposed to be interested in machines or math. But maybe most prevalent of all was the certainty that young women were not supposed to be competitive, especially in sports.

Feminine young women and girls did not sweat, or at least did not admit to it. To do otherwise would have compromised their ability to succeed at what society deemed the one most important achievement of their lives: to get married.

Those stereotypes, held up as fact not only by men but also by many women, did women a huge disservice. They relegated women to a narrow framework of occupational possibilities and, it must be said, kept them under the thumbs of men, who, as a result, controlled the realms of business, medicine, the arts, and, of course, professional athletics.

Then in June 1972, Congress passed a set of amendments to existing federal education laws. The ninth of those, Title IX, prohibits discrimination based on gender in schools and colleges that accept federal funds, and has done more for women's rights than anything since suffrage.

While its supporters saw the desperate need to create equality for female students, Title IX was not foreseen as the landmark women's civil rights legislation of the 1970s when it was adopted. Instead, many expected the Equal Rights Amendment to the Constitution, which was passed by Congress and sent to the states for ratification the same year, as the real game-changer for women. But the ERA never became law (Utah rejected it, under pressure from The Church of Jesus Christ of Latter-day Saints), and Title IX evolved into the groundbreaking legislation of the era for women's rights.

While it applied to education in general, the law's effects were most impressive in athletics. After Title IX was passed, the number of girls playing high school sports rose from 294,000 in 1971 to 2.8 million in 2002, and the number of women athletes in colleges increased fivefold.

But getting women onto basketball and volleyball courts, tracks, baseball and soccer fields, wrestling mats and even the gridiron has had an even greater impact by moving women into better competitive positions in careers. It's easier to break into the boys' clubs when you have had similar experiences on playing fields and speak the language.

Before 1972 women didn't understand what it meant to be a "team player" or why it was important. Title IX gave them that knowledge, and it opened doors not just to the locker room but to board rooms across the nation.