The United States and Australia may be considered the two powerhouses in Olympic swimming, but China is expected to be right there at the top of the podium.
The Asian nation is always among the top of the leaderboard in total medals at the Olympics. Last Summer Olympics in Tokyo, China finished with 38 golds, just one shy of the United States for the most at the 2020 Olympics. Of those 38 first-place finishes, three of them came in the pool.
With that said, there is an asterisk next to those medals.
China is in the midst of a doping scandal after a number of its swimmers tested positive for the banned substance trimetazidine (TMZ). According to reporting in April of this year by The New York Times, 23 swimmers had trace amounts of the substance in their system before the Olympics.
Despite these findings, a number of these same athletes are going to be in Paris, competing for a chance at a gold medal.
Here's everything you need to know about the China swimming doping scandal.
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At the start of the calendar year in 2021, 23 Chinese swimmers tested positive for TMZ. It was about seven months before the 2020 Tokyo Olympics, which were delayed a year due to COVID-19.
Despite how long ago these tests were taken, it was not revealed until April 2024 that these swimmers failed to pass a substance test.
The swimmers were not sanctioned by CHINADA, China’s anti-doping agency, as traces of TMZ were reportedly found present in the hotel the swimmers stayed at. The agency concluded that the readings were caused by "an isolated mass incident caused by athletes’ unknowing consumption of food contaminated with TMZ," and "no fault or negligence" with any of those involved was found.
Ultimately, the World World Anti-Doping Agency accepted China’s explanation for the failed tests, citing that the accidental contamination caused "very low levels" of TMZ.
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The neglect by CHINADA and the decision by WADA have left numerous countries and organizations furious at the decision. Travis Tygart, CEO of the United States Anti-Doping Agency, or USADA, called the news "crushing," and that the world and Chinese anti-doping associations had "secretly, until now, swept these positives under the carpet."
Meanwhile, CHINADA has accused USADA and the New York Times of making "false accusations and misleading, defamatory reports."
Trimetazidine, also known as TMZ, is a "medication used to treat heart-related conditions," according to WebMD. The substance "allows for more blood flow to your heart and limits quick changes in your blood pressure. This can help lessen chest pain from blocked blood vessels."
WADA banned the use of TMZ in all sports in 2014. It’s considered a "hormone and metabolic modulator," which falls into a category of drugs that are illegal for athletes to use.
The reason why athletes take TMZ is to potentially help their hearts work more efficiently. In sports, like swimming, that require a large amount of physical energy, and it can give someone a competitive advantage.
In total, there were 23 Chinese swimmers who tested positive for a banned substance after the last Summer Olympics.
Of that group, 11 are back representing China at this year's Summer Olympics in Paris. It includes Olympic champions Zhang Yufei and Wang Shun, as well as world record holder Qin Haiyang.
Here is a full list of the Chinese swimmers who were involved in the controversy and are participating in the Paris Olympics.