In an extensive interview with TIME published on Thursday, Williams alluded to her muscular physique as one of the reasons why she’s been frequently targeted for random drug tests by the United States Anti-Doping Agency.
“Look at me,” Williams told the magazine as she looked at her reflection in a mirror. “I was born this way. They’re like, ‘Oh, she can’t be that great, she must be doing something.’ “
Williams has a point, as USADA records show she’s tested far more than other top-tier female and male tennis players.
The agency tested Williams five times in 2018, three times in 2017 and six times in 2016. Her sister, Venus Williams, has been tested twice this year, while 25-year-old Sloane Stephens has only been tested once. Stephens won the U.S. Open in 2017 and is currently ranked No. 3 in the world.
Williams’ comments to TIME echo other complaints concerning the USADA she has made over social media. In June, she took to Twitter to call out the agency and accuse them of discrimination.
“… And it’s that time of the day to get ‘randomly’ drug tested and only test Serena. Out of all the players it’s been proven I’m the one getting tested the most. Discrimination? I think so,” the 23-time Grand Slam winner tweeted. “At least I’ll be keeping the sport clean #StayPositive.”
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Williams — who married Reddit co-founder Alexis Ohanian, 35, in November 2017 — added in a follow-up tweet: “But I’m ready to do whatever it takes to have a clean sport so bring it on. I’m excited.”
Leading up to her loss against Angelique Kerber at Wimbledon this year, Williams told reporters that she wished the agency would “just test everyone equally.” In an interview with Sports Illustrated, Williams affirmed she is not against anti-doping tests. She just doesn’t like feeling she is singled out.
“I’m totally OK with testing and I encourage it,” she said. “It’s just about being equal and not centering one person out.”
“Some days, I cry,” she said. “I’m really sad. I’ve had meltdowns. It’s been a really tough 11 months.”
Williams experienced a life-threatening pulmonary embolism after the birth, which kept her in bed for weeks.
Following her loss at Wimbledon, coming just ten months after giving birth to Alexis Olympia, Williams said she hadn’t lost confidence that she would add more championships to her already impressive legacy in the future.
“It was such an amazing tournament for me,” Williams said after the heartbreaking loss. “I was really hoping to get this far. It’s obviously disappointing, but I can’t be disappointed. I have so much to look forward to. I’m literally just getting started.”