Venus Williams is telling me about the time she and her sister Serena escaped from a vegan wellness retreat in search of steak. "We went to the opening lecture, looked at each other and decided we should go out to a restaurant," laughs the seven-time tennis Grand Slam champion. "We had steak and chocolate cake – I don’t even eat dessert! We were staying for three weeks, so we knew this was it!"

She confesses this to me from her hotel room at Claridge's, where she’s wrapped in a white robe having her hair braided before flying home to the US later the same day. She’s only in London for 48 hours for meetings and to be photographed for Bazaar’s cover; but, despite the jet-lag, she’s in fine spirits and a thoughtful mood.

In person, she has extraordinary presence: she’s tall at 6’1” and self-assured, yet what surprises me is how quietly spoken she is. Once we get chatting, she is funny and animated, smiling and cracking jokes, though she knows exactly what and how much she wants to say, after years of experience being in the public eye.

And though she may jest about the steak, the wellness retreat in question was a transformative moment in Venus’ life. In 2011 she was diagnosed with Sjögren’s syndrome, an incurable autoimmune disease whose symptoms include pain, numbness and fatigue. Seeing her struggle with the diagnosis, Serena suggested they attend the retreat to see if making some changes could help manage the condition. It had a huge impact, with Venus becoming vegetarian and completely rethinking her attitude to her body; she now follows a plant-based and sugar-free diet to help alleviate the symptoms of exhaustion, and says her condition is manageable.

venus williams
Richard Phibbs
Alpaca dress, Carven; white gold and diamond earrings, Van Cleef & Arpels

Her interest in wellness since then has prompted her to write a book, Strive, an eight-step programme for physical and mental wellbeing released this month. "I want to help people have fun being healthy," she says. "It shouldn’t be hard, or a horrible journey."

Of course, as a five-time Wimbledon champion with four Olympic gold medals to her name, Venus knows how to overcome physical challenges. Even so, she says that Sjögren’s syndrome tested her in a way she hadn’t experienced before. It was the extreme fatigue that affected her the most. "I had all kinds of symptoms, but that was very challenging as an athlete. When you crash, you go so hard that you can’t get up, literally," she says. "But I still got up, because I had to. Lying in bed is not fun. There is no substitute for being well. I had to change my pace."

For the first time in her career, she couldn’t just power through the situation. "It took seven years before I was diagnosed," she says. "It was a head-trip. I wasn’t reaching my full potential and I didn’t know why. Was I working too hard? What was I doing wrong? That takes its toll and it’s not easy to walk out there when you don’t have much to give." In her book, she reveals that, in the past, there has been the misconception that she is ‘superhuman’. So, when she was finally diagnosed, it was a relief. "Like, 'Oh, I’m not crazy'."

venus williams
Richard Phibbs
Organic cotton moleskin dress, Marni; leather heel, Miista; jewellery all Van Cleef & Arpels

"I hadn’t felt myself for a while," she admits. "But at the same time, it was hard to accept. I’m used to doing whatever I want, working hard and staying fit. To realise that it’s not something you can work through, that this is your life now... that was hard." She relied on the mental strength she had developed in years of competitive tennis to keep going. "Being mentally strong is so important," she says. "Not just for sport, but for life. You’ve got to make it out here, nobody is going to make it for you."

"Sport teaches you how to cope with everything you’re going to have to deal with in life"

It’s evident to see in person – she’s incredibly calm, contained, and sure of her abilities. "I can deal with a tonne of pressure," she continues. "Sport teaches you how to cope with everything you’re going to have to deal with in life – stress, lack of confidence, figuring out how to perform, how to come back if you fail... Athletes do make better choices [in those moments]."

Venus says that she likes to tackle any problems head-on, rather than let them linger. "When I was younger, if I had a bad practice, I’d have a horrible day," she explains. "After a while I was like, 'I can’t live like this anymore. I’m tired of being so upset.' Stress is a heavy matter, but it’s a moment in time. You can’t carry it with you, so I compartmentalise it. Whatever happens, everything is going to be OK. You don’t want to die with that stuff!"

venus williams
Richard Phibbs
Viscose and satin dress, Ferragamo; Calfskin brogues, Gianvito Rossi; rings, Tiffany & Co.

The topic of mental health and sport was at the forefront of this year’s Olympics in Paris, highlighting the crushing responsibility that comes with being at the top of your game – and staying there. The British swimmer Adam Peaty made a return at this year’s games after taking time out in recent years because of periods of depression and struggles with alcohol. "I got to a point in my career where I didn’t feel like myself. I didn’t feel happy swimming. I’ve had my hand hovering over a self-destruct button because if I don’t get the result that I want, I self-destruct," he said last year. Meanwhile, the US gymnast Simone Biles was back on gold- medal-winning form after she withdrew from the 2021 Tokyo Olympics for the sake of her mental health.

Venus says she has always made a concerted effort to look after herself in this way. "Definitely, proactively. That means training yourself to be able to deal with issues that you’re going to have in your life and getting ready for what might come."

Has it ever all got too much for her? "I have never neared a burnout, although last week I said I needed a permanent vacation! But I was going too hard for a few months with my schedule. That was my decision. We don’t always have a choice, but periods of rest are so important."

While anxiety is not something she suffers from regularly, she does occasionally struggle with the public-facing part of her job. "I think all of us have situations that make us anxious," she says. "I don’t like to be around people, so that’s one thing. In July, I had to do a segment on-stage at the ESPYs [a US sports awards] and I was like, 'Oh my goodness, I can’t do this.' I don’t like to perform in public in front of a camera, but it’s just a moment of discomfort. I don’t have the level of it where it’s crushing."

venus williams
Richard Phibbs
Merino silk knit cardigan with crystal embellishment, tulle lace-up corset with sequin flowers, Simone Rocha; heels, Christian Lobuoutin

As well as looking after her mental health, she exercises most days. "I do weights, and I swim in an Olympic-size public pool near my home surrounded by pines in Florida." And she plays tennis regularly, taking part in the US Open just last year. "I’m still training, not every day like before but I’ll always need to be on court," she says. "It’s a wonderful way to stay fit, burn calories and have great legs and arms! If you want to look good, play tennis. It doesn’t look like work but it’s exhausting. I will do that as long as I have cartilage! If I keep playing, hopefully the ageing process won’t start...!"

These days, her time is also taken up with running her award-winning interior-design company V Starr Interiors, which she founded in 2002; Happy Viking, her plant-based protein-powder range; and Palazzo, an AI-powered interior-design platform. And she has several film projects in the pipeline, including En Garde, an adaptation of Jewell Parker Rhodes’ 2020 book Black Brother, Black Brother, which she is working on with Serena and Alexandra Milchan, the producer of Tár. "I do love storytelling," she says. "It is a new thing."

"I have never neared a burnout but I was going too hard. Periods of rest are so important"

She discovered her taste for film after working as an executive producer on the 2021 biopic King Richard, which focuses on her father’s determination to turn his daughters into tennis stars. He had them training on the tennis court as soon as they could hold a racket, and Venus made her professional debut in 1994 aged just 14. It’s clear that her parents had ambitious plans for Venus and Serena (who has won 23 Grand Slams herself ) to succeed in tennis, but she regards her time growing up with affection.

Venus describes her upbringing in the city of Compton, California, as "fantastic", and says of her parents: "They were the best. They were very protective and made sure we had a childhood – you can’t get that back. So when it came to extremes and it was going too fast, we would slow down."

If she ever injured herself, she would pretend she hadn’t, as she knew her parents would make her take time out from tennis. "They’d be like, 'Is your leg hurting?’ I’d say, 'No! I’m fine.' Then when I was out there [playing], I’d be like, 'OK, my leg hurts!' They didn’t push us hard." The couple also insisted that their daughters continued their studies at school, and Venus has degrees in fashion design and business administration.

venus williams
Richard Phibbs
Knitted loop coat, Stella McCartney; Nappa leather heels, Jimmy Choo, jewellery Van Cleef & Arpels

The Williams parents divorced in 2002, and Venus’ eldest sister Yetunde was tragically murdered in Compton in 2003, but the family remains very close and she, Serena and her other sisters Isha and Lyndrea see each other often. "There’s no place like home," Venus says. "We hang out all the time. The distance doesn’t really exist." As for Serena, although they played professional doubles together for years, and against one another in singles matches, Venus insists that when they talk, tennis is almost always off the table. "We just gossip. We’ve both been on a very stringent eating programme recently, so we’re supporting each other with that."

She loves to spend time with Serena’s daughters, seven-year-old Alexis Olympia and one-year-old Adira. "It’s wonderful," says Venus. "You don’t have to be the one doing the disciplining. You get to come for the fun parts. Although, as soon as I go over there the older one wants me to start running around. Who wants to do that! I’m so tired of running. Can’t we sit and play Lego or something?"

She isn’t up for talking about her love life, but in 2022 she said, "I’ve had a single life for a long time and I think it’s really easy to get stuck in single life and sometimes – at least for me – harder to get out." However, of her dog, Harry, a Havanese, she tells me, "We love to spend time together. We’re codependents and it’s great."

Venus still understands the elite-sport mindset, and found the Olympics almost too much to bear. "It’s hard to watch," she says. "There are not a lot of chances to take part. You get one moment in time, maybe a second, potentially a third... my heart goes out to them." While Venus is the most decorated tennis player in Olympic history, she didn’t miss taking part this year. "I played a lot of them. I don’t feel like I’m missing out by not being there. But the Olympics were pretty special... Just to have been involved in something much bigger than yourself is amazing. All the moments make my journey, and I’ve had so much fun. I cherish all of it." And so she should.

‘Strive’ by Venus Williams is out now.