As Lucie Marie Kretzschmar, a beach handball player for Germany, was competing in a tournament in Romania, she noticed a front-row spectator filming intently with his phone.
When she was off the court, she saw that he was zooming in on the bodies of female players, who were clad in small bikini bottoms as the sport’s federation requires. She then saw him at two other games, recording players again.
The 2019 tournament left a question for Ms. Kretzschmar and her teammates: Were the spectators there to watch them play as elite athletes or to gawk at their bodies?
“This made me really think, ‘OK, maybe they’re not watching us as professional players,’” Ms. Kretzschmar said, but rather as “their free-time activity of watching some girls in bikinis.”
Event organizers eventually asked the man to leave, but the team’s question persisted, along with other concerns about sexism and double standards affecting female athletes at every level of competition and across sports like gymnastics, badminton and tennis.
On Wednesday, following international outrage over the issue, Hassan Moustafa, the president of the International Handball Federation, said new rules were “very likely” to be enacted.
Last month, Norway’s women’s beach handball team was fined 1,500 euros for wearing shorts instead of bikini bottoms to the bronze medal championship game in Bulgaria, a penalty that drew widespread condemnation, a petition against the rule and an offer from the singer Pink to pay the fine.
Teams from Germany, Sweden, Denmark, France, the Netherlands, Spain and American Samoa have increased the pressure on the I.H.F., the sport’s governing body, to change its rules.
The I.H.F. requires that women wear bikini bottoms “with a close fit and cut on an upward angle toward the top of the leg.” The sides of the bikini bottoms must be no more than four inches. Men, on the other hand, can wear shorts as long as four inches above their knees as long as they are “not too baggy.”
Norway’s handball federation last week proposed that the I.H.F. scrap its bikini bottom rule, citing the double standard in attire for male and female athletes. “The players should have two to four options to choose from,” the proposition recommends.
So far, the I.H.F., which is based in Basel, Switzerland, has said it could not make any changes until its international conference in November.
The federation decided to require that female players wear bikini bottoms because those were the rules for beach volleyball, which is played on the same surface, Mr. Moustafa said in a statement.
The I.H.F. also said it was “unfortunate” that the Norwegian players wore shorts, against league rules, during the Olympics.
“Due to the timing of their protest and campaign, the achievements of the athletes were simply overshadowed,” the organization said.
The Danish Handball Federation, in a letter to the I.H.F. in May, wrote that several Danish players had decided not to compete in this year’s tournament because they felt ill at ease in bikinis.
“Many feel downright uncomfortable, having to wear such minuscule attire, which does not cover much more than underwear,” the letter said. Denmark’s federation applied for an exemption to the rules, so that its players could wear shorts, but the request was denied, the organization said.
Morten Frandsen Holmen, the coach of the Danish women’s team, said that “If you type ‘beach handball’ into Google, you can find thousands of photographs of women that make you think, ‘Is it important for the sport that we have this uniform?’” In interviews, players from several teams said that worrying about bikini bottoms slipping out of place distracted them from the game.
Kare Geir Lio, the head of the Norwegian Handball Federation, said Norway had since 2006 repeatedly complained about the requirement to the I.H.F., on the grounds that some women felt embarrassed by having so much of their bodies exposed and that the requirement was insensitive to some cultural norms.
In American Samoa, for example, where many people dress conservatively, the bikini requirement made youth beach handball players feel particularly uncomfortable, players and coaches in the region said.
When the territory’s youth beach handball team won the 2017 regional championship, the players, whose ages ranged from 15 to 17, did not want to wear bikini bottoms to compete at the next level, according to C.J. Sagapolutele Floor Sr., the head coach of the team.
The I.H.F., however, informed the league that the players, who usually wear shorts, had to wear the bikini bottoms if they wanted to compete in the world championships in Mauritius.
“I first had to get permission from the parents,” said Mr. Sagapolutele Floor, who is also the vice president of the Oceania Continent Handball Federation. The parents ultimately agreed, but the girls felt embarrassed when they saw photos of themselves from the game, including ones where their legs were open, he said.
Prospective athletes were choosing not to join the league because of the apparel, he said. “It doesn’t seem right that the men can wear shorts and a jersey and the women must wear a bikini and sports bra,” he added.
Naomi Mataua Aasa, a beach handball player for the American Samoa team, said the rule had caused humiliation for female players.
The girls encountered sexual harassment from male players because of the uniforms, she said, and photographs posted on social media included embarrassing shots of their bodies.
The uniform rules, she said, indicated that “we are there to put on a show rather than being marked as athletes equally.”