Seven-time World Record Champions, Craig and Paul Pumphrey, return to the scene of their greatest triumphs: the ISKA World Breaking Championships. Meanwhile, the current World’s Strongest Man, Phil Pfister, sets out to defend his title and establish new world records. But human strength and power also manifests in ordinary people in extraordinary circumstances, like a mother who lifted a car off her injured child. Examine the physics and physiology of the most dangerous, yet surprising Strongman feat of all time. It’s not shattering steel or stone, not braving fire or ice, but having to inflate a hot water bottle with nothing but lung power. As the bottle expands, the pressure on the lungs is so great it could literally bend steel. While attempting this feat, legendary strongman Franco Columbo’s right lung burst entirely and his left lung haemorrhaged so severely he was given the last rites in hospital. That’s the thing about natural manpower – just when you think the upper limit has been reached, someone new steps up to the fore and re-defines what many believe to be “humanly possible. The ultimate question is: is there a limit at all to the human capability?

Friday 14 March, 9.30pm on National Geographic

Steroids are one of the most controversial issues in sport for one simple reason. Not because they are illegal, unfair and potentially deadly, but because they work. This unprecedented exposé reveals for the first time not just what steroids do, but how and why they work. Although the science is solid, this is no clinical study. We’ve seen what happens outside the body – in freakish detail – now, for the first time ever, stunning CGI reveals what’s happening inside. Chemistry meets anatomy here, with spectacular and sometimes tragic consequences. With “designer” steroids and genetic manipulation entering the fray, the sky truly is the limit. Every generation of synthetic hormones is more powerful than the last. What do they tell us about the future of human performance? How long do they take to transform a body and what is the mechanism? How can you tell between a cheater and a genuine athletic “freak”? What are “designer” steroids and how are they changing the performance landscape? Is direct genetic manipulation the way of the future? If so, have we reached an era of unlimited human potential?

Friday 7 March, 9.30pm on National Geographic