Serena Williams' Comeback Ignites Debate on GLP-1s and Performance Enhancement in Elite Sports
核心洞察
Serena Williams returned to professional tennis at Queen's Club, winning her doubles match while openly using GLP-1 (搜索) drug Zepbound for weight management.
WADA has been monitoring semaglutide and tirzepatide since 2024 to detect potential patterns of misuse in sport, though they remain unprohibited.
Experts note GLP-1s' muscle-wasting effects may complicate classification as performance-enhancing, while new formulations with fewer side effects could shift the debate.
Serena Williams' return to professional tennis this week at the Queen's Club grass-court tournament in London has done more than reignite interest in the sport — it has placed a spotlight on the growing intersection of GLP-1 (搜索) receptor agonists and elite athletic performance. The 23-time Grand Slam singles champion, now 44, partnered with Canadian teenager Victoria Mboko to defeat the No. 3 seeds Erin Routliffe and Nicole Melichar-Martinez 7-6(2), 6-2, all while managing her health with Zepbound (tirzepatide), a drug she has openly endorsed.
Williams' comeback comes roughly one year after she first disclosed using GLP-1 (搜索) medication through Ro, a telehealth company for which she serves as a paid ambassador and in which her husband, Reddit co-founder Alexis Ohanian, is a major investor. "After having two kids, I wasn't able to be at a weight that was healthy for me," Williams told the "Today" show in 2025. She later told Oprah Winfrey: "I couldn't beat the weight. It was the one opponent I couldn't beat."
WADA Monitoring and the Performance-Enhancement Question
The World Anti-Doping Agency (WADA) placed semaglutide and tirzepatide — the two main classes of GLP-1 (搜索) drugs — on its monitoring program in 2024. A WADA spokesperson confirmed: "Semaglutide and tirzepatide were added to the Monitoring Program to track patterns of use in sports in and out of competition. The Monitoring Program includes substances which are not on the Prohibited List, but that WADA wishes to monitor in order to detect potential patterns of misuse in sport."
For a substance to land on the banned list, it must satisfy two of three criteria: the potential to enhance sport performance, the potential to pose a risk to athletes' health, and the potential to violate what WADA defines as the "spirit of sport." Minutes from a WADA Health and Research Committee meeting last August reveal discussions about "whether a new class addressing all types of weight management substances should be created, not only for weight category sports but also weight-sensitive ones (e.g. gymnastics, figure skating, cycling)."
Novo Nordisk, which manufactures GLP-1 (搜索) drugs, stated: "We are supportive of the WADA recommendation, and we strongly discourage use/promotion outside the indicated population and approved label." Eli Lilly, which produces tirzepatide, did not respond to requests for comment.
The Muscle-Wasting Complication
A key factor complicating any potential classification of GLP-1s as performance-enhancing is their effect on lean muscle mass. Studies of GLP-1 (搜索) patients have shown that muscle loss occurs alongside fat reduction, which for athletes would do the opposite of enhancing performance. This has prompted research into adjunctive therapies.
VERU, a Miami-based pharmaceutical company, announced in 2023 that its experimental drug Ostarine (enobosarm) had shown early success in clinical trials to prevent muscle-wasting among elderly patients and people with diseases such as cancer. The company is currently conducting trials exploring its use in concert with GLP-1 (搜索) drugs. However, Ostarine is on WADA's Prohibited List. "It should be on the list and banned from sport because it's very effective," said Mitchell Steiner, chief executive of VERU. "It's a performance drug. Our job is to get the right indication and show the safety in a controlled setting."
Matthew Fedoruk, chief science officer at the U.S. Anti-Doping Agency (USADA), noted that future formulations could shift the regulatory calculus: "I think what you're going to start seeing is new products being introduced to the market that actually have less of those side effects, which then would be more advantageous for athletes. So this is a growing threat that I think needs to be monitored closely."
Clinical Perspectives on GLP-1s Beyond Diabetes
Beyond the anti-doping debate, physicians are increasingly viewing GLP-1s as tools for broader health optimization. Dr. Nima Afshar, a concierge doctor at longevity-focused Private Medical in San Francisco, said he has "dozens" of elite clients using these drugs to remove dangerous visceral fat. "I almost don't use the word weight," Afshar said. "Some people can carry visceral fat, but tolerate it well and have no metabolic effects — that's uncommon."
Dr. Mitch Biermann, an obesity (搜索) medicine physician at Scripps Health in San Diego, noted: "I think there are quite a lot of indications that people can justifiably use the medicine. There are just many different definitions of obesity now."
Research has shown the medications can improve heart health, liver function, and sleep quality, and scientists are probing whether these drugs could contribute to healthier aging and longevity. Exercise physiologist Pat Davidson, who is using the investigational GLP-1 (搜索) drug retatrutide (still in development at Eli Lilly), told Business Insider: "It's the most powerful drug we've ever seen for helping people lose body fat. You are never putting that genie back in the bottle."
Williams' Personal Experience
Williams lost 34 pounds after the birth of her second child in 2023 using GLP-1 (搜索) medication. "My joints are so much lighter," she told Winfrey. In a Super Bowl advertisement for Ro, she said she can move more easily and enjoy steadier blood sugar levels throughout the day while training. Reflecting on her late career, Williams expressed regret: "I wish I had done this while I was still playing. It would have made such a big difference for me and my career."
Williams' communication team declined to comment on the debate about whether GLP-1s could be banned. If the drugs were to become prohibited, athletes could theoretically apply for a therapeutic use exemption (TUE), with diabetes being the most likely qualifying condition.
As Williams continues her comeback — with expectations extending beyond Queen's Club and potentially into singles play at Wimbledon, which she has won seven times — the conversation around GLP-1s in sport appears poised to intensify alongside her return to the court.