Serena Williams is not holding back about using weight loss medication. Article continues below advertisementSerena Williams Wishes She Used GLP-1 As An AthleteCraSH/imageSPACE / MEGAWilliams recently opened up about using Ro, a GLP-1 for weight loss, in an interview. Williams recalled being on the tennis court a few days before the interview and “having fun” with it. She also counts it as a win that many other people are now being more open about using weight loss medication. The star coach revealed that he was worried about Williams’ weight because of how it would affect her game and not her appearance, and it often resulted in fights between them.