More than a century after women were first allowed to compete in the Olympics, the run-up to the 2012 London Games has been fraught with controversy over what, exactly, female athletes should wear.

Beach volleyball players will be able to wear more clothes, rather than less, for the first time in Olympic competition — free to swap their bikinis for more modest shorts and sleeved tops. The change, announced in spring, was designed to accommodate countries’ cultural beliefs but, in the process, has devastated legions of male fans who cheer the sport’s skimpy attire as much as its athleticism.

Meantime, female boxers, who’ll make their Olympic debut in London, helped deal a knockout blow to an attempt to make them wear skirts in the ring rather than trunks. The idea, proposed by the Amateur International Boxing Association, was intended to help TV viewers distinguish women from men.

“I really didn’t understand that,” said Claressa Shields of Flint, Mich, 17, the youngest member of the U.S. boxing team, following a workout in east London on Thursday. “It was to help separate the men from the women. But we got different names! Women got breasts! We got butts! Can’t you tell which one is who?”

Gloria Peek, 62, a member of the U.S. boxing team’s coaching staff, was dumbfounded when the idea was proposed.

“This is a pugilistic sport, a combative sport. And you want to put sex into it? For what reason?” Peek asked. “The skirt equates to sex; it equates to nothing else. How are you going to take that and put it into a gladiator sport? And what does that have to do with it?”

Under the compromise that resulted, female boxers can wear skirts if they like but it won’t be mandatory. That suits Shields just fine.

“If you want to wear skirts, go ahead,” said Shields, a 165-pound middleweight. “But if you don’t, just let us be normal. I’m not gonna wear a skirt!”

And those aren’t the only Olympic sports with their proverbial knickers in a twist over the issue of women’s garb.

Much like boxing, badminton’s international governing body was forced to retreat from a new dress code that would have required female Olympians to wear skirts rather than shorts. The stated goal: to attract more fans through “a stylish presentation of the players.”

Following howls of protests, skirts were made optional.

In one sense, the angst over female athletes’ attire in a handful of Olympic disciplines is a mere footnote to a 17-day global competition that celebrates the best in sporting achievement and sportsmanship.

But in another sense, it offers a window on the complex and competing interests involved in staging the $18 billion Games: issues of marketing, gender politics and cultural diversity. And on the eve of the 2012 Olympics, they have collided on the peculiar playing field of women’s closets.

That’s familiar terrain to dress historian Patricia Campbell Warner, considered the leading authority on women’s clothing in sports and author of “When the Girls Came Out to Play: The Birth of American Sportswear.”

When women were first allowed to compete in the Olympics, at the 1900 Paris Games, they were required to wear clothing that covered their legs, which explains why their repertoire of events consisted of golf, tennis and croquet, Warner explained in an e-mail exchange.

Still, that represented a major step forward from the ancient Olympics, in which women weren’t allowed to compete under penalty of death. Even the founder of the modern Games, Baron Pierre de Coubertin, had little use for women regardless of their outfits, saying: “I do not approve of the participation of women in public competition. In the Olympic Games, their primary role should be to crown the victors.”

Not until 1920 did the Olympics allow women to compete in swimming.

With the addition of women’s boxing, the London Games will mark the first Olympics in which women are allowed to compete in every sport contested by men.

To Warner, the notion that modern-day boxers and badminton players would be forced to wear skirts hearkens back to a century’s old era, in which women’s Olympic participation was largely dictated by dress.

But if women’s boxing and badminton averted a potential step backward on the eve of the 2012 Games, beach volleyball took a bold step forward in giving women the right to compete in less revealing outfits, in the view of U.S. Olympian Jennifer Kessy.

“We want women of all different religions and everyone from around the world to be able to play our sport,” Kessy said this week. “To not be able to because of the attire is not okay for us. So the fact that women can wear more modest garb is something great.”

Said Kath Woodward, a British sociology professor and author of “Sex, Power and the Games”: “Really, I think there are more weighing things to worry about. But in a way, it is quite important. Women should be able to wear shorts and vests rather than wearing bikinis. It trivializes women; they get called girls and sexualized.”

That said, the U.S. women plan to stick with their bikinis for London, although they’ve packed leggings and long-sleeved fitted shirts in case temperatures plunge for their matches, which will be held late at night to attract the biggest possible TV audience in the United States.

April Ross, Kessy’s teammate, laments the fixation on bikinis, which she considers market-driven hype.

“As an athlete that has played beach volleyball a long time, I appreciate the hard work we put in and how grueling the sport actually is, so I couldn’t care less what we wear while we play,” Ross said. “I understand that other women have other concerns than we do. So wear shorts, wear pants. I don’t care. And I don’t think anyone else should care, either.”