2025 World Championships
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Many times in sports, it is the outliers who have led to rules changes. Wilt Chamberlain’s dominance led a wider lane in basketball and new offensive goaltending rules. Mel Blount’s physical play limited the amount of contact NFL defensive backs could make down field. David Berkoff forced swimming to institute a maximum 15 meters underwater rule.
Now, Chinese 12-year-old Yu Zidi is on the verge of doing the same.
Brent Nowicki, the executive director of World Aquatics, said this week at the World Championships that the organization would review its age-limit rules in light of the Chinese phenom’s success.
This week, she became the youngest-ever medalist at a World Aquatics Championships when she swam a prelims leg on China’s 800 free relay. She has already twice come very close to individual medals, finishing 4th in the 200 fly and 4th in the 200 IM. She missed the medals by .31 and .06 seconds in those events, respectively, and still has maybe her best medal chance, the 400 IM, to come.
“I didn’t think I’d have this conversation, but now I think we have to go back and say is this appropriate?” Nowicki said this week in Singapore, as reported by the Associated Press. “Is this really the right way to go forward and do we need to do other things? Put other guardrails up? Do we allow it under certain conditions? I don’t know the answer.”
Nowicki said that Yu was “great,” and also added that officials had to be “careful” about the age rules.
Current World Aquatics rules say that athletes must be at least 14 years of age on December 31st of the current year to compete at the World Championships or Olympic Games in swimming. It allows exceptions in cases like Yu, where swimmers have achieved at least the ‘B’ Standard Entry Time in the respective event.
The rule was instituted after the 2015 World Championships, when Bahrain entered 10-year-old Alzain Tareq in the 50 free and 50 fly. Tareq didn’t have a qualifying time but was entered under Universality rules that allow all countries to enter swimmers into the World Championships without entry times if they have no qualified athletes.
She finished 105th out of 113 legally-finishing athletes in the 50 free and 64th out of 64 athletes in the 50 fly. SwimSwam could not identify any international results for her since the 2019 Asian Age Group Championships when she was 14.
Rules since then require countries to send the top swimmers by FINA Points in the country to the Olympic Universality program.
The current rules don’t address athletes who would swim on relay teams, nor do they address the significant drops that swimmers at this age can see even in the course of a few months. Yu, for example, was 2:10.63 in the 200 IM and 2:06.83 in the 200 fly at the Chinese National Championships, and was faster than both of those times at Worlds.
In all, the conversation reinforces Yu as an outlier not only that she is capable of qualifying for the World Championships, but that she is capable of competing for and, in at least one case winning, medals.

LET THE 12 YEAR OLD SWIM. WTF? I WAS 9 AND WENT A 50.12 IN 100 YARD BACKSTROKE AND NO ONE COUNTED IT. WORLD RECORDS ARE A JOKE.
My two cents…
Its worth considering adjustments that can be made, but ultimately not going to be hugely useful, imo.
If you’ve got a kid who is under the age limit but potentially capable of medaling, many countries can just forge the documents to age them up a couple years.
How many remember Karen Muir who broke her first of 15 world records at age 12. As I recall from the time, her youthful age impacted which meets she could participate in (and, subsequently, the fact that she was from the Union of South Africa meant that the world record holder couldn’t participate in the Olympics).
There should not be age discrimination against young swimmers. Otherwise, the winner should not be called World champion. Just called them adult champion….. If there are legal age group competition all over the world, why you bar them from swimming world championship if they are good enough? This is more like a 60 years old master swimmer making A cut, will you let him/ her swim? If yes, why not the younger one?
This is ridiculous.
It’s okay to have a child swimmer, but who can’t be too good. It’s ridiculous.
If the rules are in place to help prevent exploitation of very young children then exceptions for fast children are complete BS.
I think it’s very fair to assess whether having a pre-teen compete at a competition like this is the best thing for their mental health.
Even much older swimmers with higher levels of emotional maturity struggle mentally at these competitions.
In some ways I feel like it would be almost easier when your young. When you get older you might put more thought and pressure into it.