A transgender cyclist has defended her world title win after Donald Trump Jr called it 'bulls---'

• Transgender cyclist Rachel McKinnon has defended her world title title win at the Masters Track World Championships after criticism from Donald Trump Jr.
• Trump tweeted that such "bulls--- will destroy women's sports" and that he was "sorry to all female athletes who spent their lives mastering their games."
• McKinnon cited the tweet as reason for a number of hate messages she received, whilst later adding: "Y'all don't have a problem with testosterone levels, you have a problem with trans women period."
• The Canadian rider was born a biological male but identifies as a transgender woman, and has been competing in female events since 2016.
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Transgender cyclist Rachel McKinnon has defended her world title win at the Masters Track World Championships on Saturday after Donald Trump Jr. said that such "bulls--- would destroy women's sport."

McKinnon, a 37-year-old Canadian, won gold for the second year running in the female 35-39 age category sprint, while also setting a new world record in qualifying, making it around the 200m course in just 11.649 seconds.

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Trump Jr. hit out at McKinnon on Twitter after her victory, saying: "This BS will destroy women's sports and everything so many amazing female athletes have worked their entire lives to achieve. I couldn't care less how you identify, but this isn't right."

Trump also later tweeted that he was "sorry to all female athletes who spent their lives mastering their games."

McKinnon responded by quoting Trump's second tweet alongside the caption: "Oh THIS explains the explosion of hate messages I'm getting!!"

She followed it up with a number of tweets in which she defended her right to compete as a female athlete, which she has been doing since 2016.

Read more: A high school girls soccer team was penalized for jerseys that said 'equal pay' during a game, but earned support for their message off the field

"I was competing prior to the IOC's 2015 update to their trans policy," McKinnon said. "I met the older, more restrictive 2003 policy.

"Y'all don't have a problem with testosterone levels, you have a problem with trans women period."

An earlier tweet read: "I'm just going to come out and say it: My body doesn't produce testosterone anymore. And it hasn't for nearly a decade. Draw your own conclusions."

Another added: "We are either full and equal women, or not. We are."

McKinnon has also come under scrutiny from fellow athletes

Transgender athletes are allowed to compete in female events so long as their testosterone levels are below "five nanomoles per litre of blood," according to rules from the International Association of Athletics Federations (IAAF).

Despite McKinnon, who was born a biological male but identifies as a transgender woman, meeting that criteria, it still hasn't stopped fellow athletes from criticizing her and her achievements.

Read more: The biggest thing critics continually get wrong about transgender athletes competing in women's sports

Former Olympic swimmer Sharron Davies, who won silver for Great Britain in the 400-metre individual medley at Moscow 1980, said on Twitter that "female rights are being eroded every single day," while cyclist Victoria Hood said, according to the BBC, that "it is a human right to participate in sport. [But] I don't think it's a human right to identify into whichever category you choose."

18-time Grand Slam tennis champion Martina Navratilova has previously also criticized McKinnon, saying in February 2019: "A man can decide to be female, take hormones if required by whatever sporting organisation is concerned, win everything in sight, earn a small fortune, and then reverse his decision and go back to making babies if he desired."

McKinnon told Business Insider at the time that such criticism was transphobic and was demeaning of her human rights.

"We should never deny people's rights because a select few, in theory, could commit fraud," McKinnon said.

"The idea we should ban all immigrants because one or two might be terrorists is the height of racism, bigotry, and xenophobia. So their argument is the very definition of an irrational fear of trans women, the dictionary definition of transphobia."