STORY: A new rule to restrict transgender women from elite swimming is the strictest ever introduced by an Olympic sports body.
World swimming's governing body FINA voted for new eligibility rules.
It effectively bars any transgender women who have gone through male puberty from competing in women's events.
FINA also agreed to establish an "open" category for some events that it says would ensure all swimmers would have the chance to compete.
Let's take a look at how the new rules work and why they're so important to the world of sport.
Why did FINA take this decision?
There have been growing calls from former swimmers and coaches for FINA to restrict the participation of transgender women in the sport.
They argue that people who have gone through male puberty have physical advantages.
The calls intensified after American swimmer Lia Thomas became the first transgender NCAA champion in Division I history.
FINA's president, Husain al-Musallam:
“It is a policy that we need to introduce in order to protect the competitive fairness of our event."
“I do not want any talented athlete to be told that they are unable to compete at the highest level. I will set up a working group that will establish an open category at some of our biggest events. FINA is leading the way, we will be the first international federation to begin this work.”
On the other side, supporters of trans participation argue that not enough research has been done.
Groups such as Athlete Ally have stated that FINA's new policy is "discriminatory, harmful, unscientific.”
Where does the rule apply?
The ruling applies to elite competitions run by FINA, such as their world championships and the Olympic Games.
It means that swimmers, such as Thomas, will not be able to compete in world championships or the Olympics.
It also impacts on who is eligible to set a world record in women's swimming.
It does not necessarily apply to national or regional competitions or lower-level meets.
The ruling also only impacts on transgender athletes in women's competitions.
Transgender men will be eligible to compete in men's races without any restriction.
What about other sports?
Other sports will be watching any legal moves with keen interest.
Many sports bodies have allowed transgender women to compete in women's events if they have lowered their testosterone levels to a certain point.
In 2021, New Zealand weightlifter Laurel Hubbard became the first transgender athlete to compete in the
Olympics in a different gender category than assigned at birth.
Earlier in June, the International Cycling Union tightened its rules by increasing the transition period for lower testosterone from 12 months to two years.
FINA’s ruling could increase pressure for similar moves inside other sports.
Cyd Zeigler, Jr. is the co-founder of LGBTQ sports site, Outsports.
"Obviously a major blow to inclusion of trans women in women's sports. When the IOC and the NCAA decided to allow different sports governing bodies to determine the eligibility of trans athletes in their sport, they opened sports up to this, where sports like rugby and swimming will ban, essentially banned trans women outright from the female category. And you're going to have other sports find different ways. / So this is chapter number 17 in a story that is going to have another 300 chapters before we're done with it."