"It was after Serena Williams' pregnancy... you can't afford to be overweight" - Ex-coach Mouratoglou opens up about American's weight gain struggles

Serena Williams’ former coach Patrick Mouratoglou recently opened up about the American's struggles with weight gain. The 55-year-old highlighted how these issues became a point of contention between the two during their partnership.

Williams and Mouratoglou first paired up in 2012, when the former was dealing with one of the worst spells of her career. However, together the duo managed to turn things around, with Mouratoglou coaching the American to 10 Grand Slam titles over the course of the next decade.

In a recent interview with The Guardian, Patrick Mouratoglou reflected on Serena Williams' weight gain struggles, saying,

“Oh I remember it very well. It was after the pregnancy – not right after; I know these things take time. I told her: ‘Listen, this is not a comment on how you look. It’s not my problem’. But tennis is a sport in which you can’t afford to be overweight.”

Mouratoglou emphasised that extra weight in tennis increased the risk of injuries, and highlighted that it was affecting Williams’ movement. He went on to add that the duo even fought about this issue at times, explaining,

“In Serena’s case, she was older – so of course the body is not going to bounce back the same as before, and the risk of injury is even bigger. We had a few fights about it. I remember she did not like when I said that because she thought I was judging her. But I kept telling her, I don’t care about your look. It’s not my job. My job is your tennis. If you want to come back to the top and make history, then we have to be very efficient on every level – including this one, which for me was the key element.”

Serena Williams gave birth to her daughter Olympia in September 2017. While the American returned to the tennis court soon after, she failed to win a Grand Slam title in the final years of her career.

Serena Williams partners with Ro for weight loss

Williams in New York City (Image Source: Getty)

Serena Williams recently revealed that she has partnered with telehealth company Ro for weight loss. The American shared that she has struggled with postpartum weight since the birth of her daughters Olympia (2017) and Adira (2023). She shared that despite regular exercise, she failed to return to her normal weight, and that the additional weight that she had been carrying was causing her joint pain.

In an interview with Elle magazine, Williams revealed that she first started taking GLP-1 medication for weight loss in 2024 but stopped soon after. In January 2025, the former tennis player partnered up with Ro and started taking Zepbound, a different GLP-1 medication and successfully managed to lose 31 pounds.

Serene Williams' admission to using weight loss drugs has been met with divided reactions, with some fans expressing disappointment at her message, while others encouraged her to make the choice best for her.