In their new BBC Radio 4 podcast, Drs Chris and Xand are on a mission to help us take better care of ourselves.

Drs Chris and Xand Van Tulleken investigate the science of exercise and the dangers of inactivity.

Is modern exercise a wellness cult? Or is it a vital cure for a world that’s struggling with ill health and stuck on the sofa? Most of us might like to get a bit fitter, but how easy is it to actually start exercising and give up sedentary habits?

In this series Drs Chris and Xand Van Tulleken examine exercise and how best to do it. How much should we be doing? How does it help our bodies? And how does our surrounding environment stand in the way of us getting fitter? Chris is challenged to examine his scepticism towards exercise. Similarly, Xand is asked to look at his new-found exercise evangelism and see what he is really running from.

Recently Xand has discovered the joys of physical activity. He’s running, cycling, heading to the gym and playing ping pong like never before. It’s been a real transformation and a way to keep on top of things after years of unhealthy living.

His twin brother Chris, on the other hand, is really feeling the aches and pains of middle age. With a busy job and a young family, he has precious little spare time for exercise. After a very active period in his 20s and 30s, Chris is now embracing his ‘Dad bod’ and sliding into a creaky middle age. Xand wants to help him turn things around. Can he do it?

In Episode 8 - Activity Revolution - the twins meet up to see how Chris is getting on with his attempts to get more active. They also have a conversation with Orla Hugueniot, public health expert and Head of Marketing at the Department of Health. She explains how government tries to communicate big messages around physical activity to the public. Chris and Xand also chat with Ryan McKay, Professor of Psychology at Royal Holloway, University of London (and Chris’ brother in law). Ryan explains how important identity is when thinking about barriers to physical activity. Has Chris finally managed to find something that will help him get a bit more active?

Presented by Drs Chris and Xand van Tulleken

Drs Chris and Xand Van Tulleken investigate the science of exercise and the dangers of inactivity.

Is modern exercise a wellness cult? Or is it a vital cure for a world that’s struggling with ill health and stuck on the sofa? Most of us might like to get a bit fitter, but how easy is it to actually start exercising and give up sedentary habits?

In Episode 7 - Have Fun, Feel Good - the twins meet Herman Pontzer, Evolutionary Anthropologist at Duke University and the author of Burn. He explains the science behind metabolism, physical activity and how we really burn calories. Meanwhile, Chris and Xand go to their local park for a game of ping pong. It’s an attempt to find a fun activity that will finally get Chris moving. Unfortunately, ping pong isn’t really Chris’ idea of fun. But what is?

Presented by Drs Chris and Xand van Tulleken

Drs Chris and Xand Van Tulleken investigate the science of exercise and the dangers of inactivity.

Is modern exercise a wellness cult? Or is it a vital cure for a world that’s struggling with ill health and stuck on the sofa? Most of us might like to get a bit fitter, but how easy is it to actually start exercising and give up sedentary habits?

In Episode 6 - Overcoming Barriers - the twins meet Dee Johnson, a therapist experienced in treating addiction disorders, including exercise addiction. She speaks with Xand about how his use of exercise might be straying over into addictive behaviour. Chris is then prompted to examine his own behaviour. What’s really lying behind his reluctance to try and get a bit fitter? We also hear from Xand and his new bride Dolly as they go out cycling on their tandem.

Presented by Drs Chris and Xand van Tulleken

Drs Chris and Xand Van Tulleken investigate the science of exercise and the dangers of inactivity.

Is modern exercise a wellness cult? Or is it a vital cure for a world that’s struggling with ill health and stuck on the sofa? Most of us might like to get a bit fitter, but how easy is it to actually start exercising and give up sedentary habits?

In Episode 5 - Endurance - it’s the day of the big race. Chris tries to run a half marathon, without having done any proper training. It’s an experience that leaves him worrying if he’s ever going to get back into shape. The twins then speak with Alex Hutchinson, writer, runner and author of Endure. Alex explains how pain, resilience and motivation all work together during marathons and other feats of endurance. He also gives Chris some tips on how to bounce back from his marathon ordeal.

Presented by Drs Chris and Xand van Tulleken

Drs Chris and Xand Van Tulleken investigate the science of exercise and the dangers of inactivity.

Is modern exercise a wellness cult? Or is it a vital cure for a world that’s struggling with ill health and stuck on the sofa? Most of us might like to get a bit fitter, but how easy is it to actually start exercising and give up sedentary habits?

In Episode 4 - Too Late to Change? - the twins meet up with their younger brother J for a session on an exercise bike. This has been a big part of Xand’s journey back to fitness. Will it inspire Chris to become more active? Chris then meets up with Sir Muir Gray, Director of the Optimal Aging Programme and an advisor to Public Health England. Muir shows Chris just how important exercise is for an ageing society.

Presented by Drs Chris and Xand van Tulleken

Drs Chris and Xand Van Tulleken investigate the science of exercise and the dangers of inactivity.

Is modern exercise a wellness cult? Or is it a vital cure for a world that’s struggling with ill health and stuck on the sofa? Most of us might like to get a bit fitter, but how easy is it to actually start exercising and give up sedentary habits?

In Episode 3 - Ultra Processed Exercise - the twins meet Danielle Friedman, author of ‘Let's Get Physical: How Women Discovered Exercise and Reshaped the World’. She explains how the fitness industry evolved since the 1950s and how it targets women. Meanwhile, Chris takes a trip to his local gym to start getting into shape for his upcoming half marathon. He also chats with David Colquhoun (Emeritus Professor of Pharmacology at University College London) about their shared suspicion towards exercise and the social pressure to be fit.

Presented by Drs Chris and Xand van Tulleken

Drs Chris and Xand Van Tulleken investigate the science of exercise and the dangers of inactivity.

Is modern exercise a wellness cult? Or is it a vital cure for a world that’s struggling with ill health and stuck on the sofa? Most of us might like to get a bit fitter, but how easy is it to actually start exercising and give up sedentary habits?

In Episode 2 - The Scale of the Crisis - the twins meet Dr Fiona Bull, head of the World Health Organization's Physical Activity Unit. She explains how the WHO is tackling the global inactivity crisis and how schools and cities need to change to meet this challenge. Meanwhile, Xand is still trying to inspire Chris to get more active, so has enlisted his help for a run around their local park. Things don’t quite go according to plan…

Presented by Drs Chris and Xand van Tulleken

Drs Chris and Xand Van Tulleken investigate the science of exercise and the dangers of inactivity.

Is modern exercise a wellness cult? Or is it a vital cure for a world that’s struggling with ill health and stuck on the sofa? Most of us might like to get a bit fitter, but how easy is it to actually start exercising and give up sedentary habits?

In Episode 1 - The Miracle Cure - the twins meet Dr Scarlett McNally, a consultant orthopedic surgeon with a special interest in the benefits of exercise. She explains just how beneficial even moderate exercise can be for our bodies and for the NHS as a whole. Meanwhile, Chris is getting nervous. He has signed up to run a half marathon, but is struggling to do even the most basic training.

Presented by Drs Chris and Xand van Tulleken

A Van Tulleken Brothers and Loftus Media production for BBC Radio 4

Drs Chris and Xand van Tulleken investigate the science of exercise and the dangers of inactivity.

Is modern exercise a wellness cult? Or is it a vital cure for a world that’s struggling with ill health and stuck on the sofa? Most of us might like to get a bit fitter, but how easy is it to actually start exercising and give up sedentary habits?

In this series Drs Chris and Xand van Tulleken examine exercise and how best to do it. How much should we be doing? How does it help our bodies? And how does our surrounding environment stand in the way of us getting fitter? Chris is challenged to examine his scepticism towards exercise. Similarly, Xand is asked to look at his new-found exercise evangelism and see what he is really running from.

Recently Xand has discovered the joys of physical activity. He’s running, cycling, heading to the gym and playing ping pong like never before. It’s been a real transformation and a way to keep on top of things after years of unhealthy living.

His twin brother Chris, on the other hand, is really feeling the aches and pains of middle age. With a busy job and a young family, he has precious little spare time for exercise. After a very active period in his 20s and 30s, Chris is now embracing his ‘Dad bod’ and sliding into a creaky middle age. Xand wants to help him turn things around. Can he do it?

The box set is available now on BBC Sounds.