It's not often that a college competitor winning a swimming race leads to international

controversy, but back in March, that's exactly what happened.

Lea Thomas, a swimmer on the University of Pennsylvania's Women's Swim Team, has become

the first openly transgender athlete to win a Division I NCAA championship.

The victory triggered changes in international rules.

Now the world governing body of swimming has voted to ban transgender athletes from competing

in women's events, unless they're transitioned by the age of 12.

But swimming isn't the only sport to rule on trans athlete participation recently.

So what are the new rules and how will they affect athletes?

Before listening to stories of our times from the times and the Sunday times, I'm Manvin

Rana.

Today, exclusion or fairness, new rules for trans athletes.

I'm Martin Ziegler and I am the chief sports reporter for the times and the Sunday times.

Martin, with all big issues, before there's any sign of change, there's always sort of

a tipping point in an argument, and it feels like in terms of trans sport and swimming

in particular, that tipping point came in March at a race for the NCAA championship in America.

20 lengths to the pool, 20 points on the line for the winner here at the NCAA championship.

The National Collegiate Athletic Association, or NCAA, is the organisation that runs sporting

competitions for American and Canadian students.

This was the first major national championship race where Leia Thomas was taking part.

Now for people who don't know who Leia Thomas is, she has become a sort of famous figure

in sport because she initially race for the University of Pennsylvania men's team when

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