Dr Xand van Tulleken spent decades known as “the bigger one”. Compared — inevitably — to his identical twin brother, Dr Chris van Tulleken, a lean, clean-eating vision of health, he was overweight. Demoralised, he accepted the idea of being “done at 65”.
But in 2021, after meeting his wife, Dolly Theis, an epidemiology researcher at Cambridge University, Xand felt reinvigorated to get his health back on track. The couple, who are expecting their first child, started exercising together and the doctor went from clinically obese — 19 stone at his heaviest — to a healthy weight of 13 stone.
Meanwhile, Chris settled into his groove as a busy dad of two with a third child on the way. He stopped exercising. Before long, the twins — now 45 — had swapped roles. Xand was worried.
So worried, in fact, that Chris’s midlife slump is the subject of the twins’ latest BBC Radio 4 series, A Thorough Examination with Drs Chris and Xand. “This series almost didn’t happen,” Chris says. “One of our beloved producers quit after the first meeting because I was so angry at Xand suggesting that I needed to do more exercise and that this would be the basis of the series.”
Xand is quick to defend himself, despite an eye roll from Chris. “I didn’t say you need to do more exercise or that you’re becoming a lazy middle-aged man. I said that after the first series on ultra-processed food my diet really changed. I’ve been doing loads more exercise. The series totally changed my life. But from your family you feel the judgment radiating over distances of thousands of miles.”
Advertisement
Chris and Xand started out as a double act presenting the 2012 children’s television show Operation Ouch!. To distinguish themselves, Xand kept his facial hair and Chris went clean shaven. They have stuck with this — useful, as the pair interrupt each other so often it can be hard to keep track of who’s saying what. Since Operation Ouch! they have presented many programmes together and separately, including Trust Me, I’m a Doctor and The Secret Life of Twins.
It was while they were filming the latter that Professor Tim Spector, the founder of the Zoe health app, revealed the pair had the biggest weight difference in twins he had ever studied and told Xand, “You are a disgrace to your genes.” “A little bit harsh,” Xand says. “But people always used to remark on it.”
Chris, on the other hand, isn’t used to taking criticism for his health. But the aim of A Thorough Examination isn’t to shame him or anyone who has “let themselves go”. “It is extremely difficult for most people to live a healthy life in the UK,” Xand says. “We don’t have the money, housing, infrastructure, opportunities, time, space or knowledge. There are forces actually stopping you from eating healthily and exercising.” Chris agrees: “The way people are is not their fault. There is almost no such thing as a lazy person A bit of nanny state-ism would be a good thing.”
Do we risk mollycoddling one another when what we really need is a wake-up call to move more and eat better? “That argument is scientifically, morally, economically bullshit,” Chris says. “If we look at the US data, everyone started gaining weight in 1975 because the food environment changed. Same with exercise: kids used to have this huge roaming area but with the rise of urban violence and changes in urban planning, they now spend 95 per cent of their time indoors.” As Xand puts it, “shame doesn’t work”.
Instead, A Thorough Examination encourages implementing small and achievable fitness goals that will make a difference to your long-term health, taking the emphasis away from weight loss and putting it on longevity.
Advertisement
You don’t need an expensive gym membership or equipment to follow their rules. One test involves counting how many times you can get in and out of a chair without using your hands in a minute. Repeat this daily to build stamina. You don’t need to devote hours to fitness either: everyone, no matter how busy, should have time to stand on one leg while brushing their teeth.
Some of the twins’ guests provide a blueprint for staying spry into old age. Take Sir Muir Gray, the 79-year-old director of the Optimal Ageing Programme and an adviser to Public Health England, who in one episode drops to the floor in a suit and tie to fire off 66 press-ups. What Gray prescribes is simple. Medium-intensity exercise, such as a 30-minute brisk walk, can reduce the risk of type 2 diabetes, heart disease, stroke and dementia.
The series’ other message is that there’s an exercise for everyone. For Chris, the breakthrough comes when he sees a group doing callisthenics in the park. This is a form of strength training that uses your body weight: moves such as press-ups and burpees. Stick with it and you’ll be lean — like the guys in the park. “I liked the way these men looked,” Chris says with a smirk. “The male physique was very appealing to me in a quasi-erotic way. Now I do my callisthenics routine, and there’s this long-term goal — I want to be able to do a handstand. I’m a very long way from that, and may never get there, but it’s OK, I’m still making progress. Then I have this medium-term goal — I’ve re-entered the Hackney half-marathon, which I failed.”
One of Chris’s most vulnerable moments is when, after next to no training for the Hackney event, he walks almost the whole route and is so embarrassed that he asks the crew to stop recording. He had taken on the race with his friends on a WhatsApp group called “Fat Dads”.
Chris says they’ve all upped their game now, “shuffling along the canal for seven kilometres” every week. He also runs with a friend. “I resisted it as he’s much faster than me. But I did it one Sunday and it was lovely. Every week he pushes me a little further.”
Advertisement
Buddying up is better than competing with yourself and others on apps that track your performance. “They can be valuable tools,” Xand says, “but they can also be disheartening. We’re 45 now and we have friends who’ve seen their Strava scores just trickle down. No matter what you do you are going to get older, so your score will go down. They found it really depressing.”
Xand’s meltdown comes in episode two when Chris doesn’t time his lap around the park: “I’m so angry at him. I’ve been saying to him that exercise is joyful. I thought, he’s going to be so inspired it’ll be like Chariots of Fire. Instead I was standing in the rain screaming at my brother.”
Although Xand admits there was a small part of him that “wanted to show Chris what it had been like for me”, he insists he never wanted to show up his twin. He wants his younger brother (by seven minutes) to be around well into their old age. “I love him and I was trying to be helpful and good.”
Listen to A Thorough Examination on Tuesdays at 3.30pm on BBC Radio 4 or any time on BBC Sounds
How to fight a fitness slump
1. Start small
Chris sets a goal of one press-up and one sit-up a day. “Once you’re on the floor you usually find you do more.” Setting more challenging goals may put you off.
2. Mix things up
Try Zumba, table tennis or a walking tour. “There may be historical walks in your neighbourhood,” Xand says.
Advertisement
3. Fit in a daily routine
Any movement is better than nothing. Lift a light weight at your desk or go on two short walks a week.
4. Mute fitness influencers
Social media can be overwhelming. Focus on realistic goals and exercises that work for you.
5. Embrace aches and pains
At first you may feel stress on joints and muscles. But injuries aside, this is your body getting stronger. You’re more likely to need a knee operation due to inactivity than overuse. Keep at it — you’ll get there.
