Is a bath full of ice cubes a therapy?

Updated: Nov 2, 2020

Exposing yourself to extreme cold makes your body more resilient, says Wim Hof, alias de Iceman. Scientists decided to find out what is true of it. TOMAS VAN DIJK

Like sardines in a can they lie side by side in a swimwear in a tub filled with snow. As if the hardship is not bad enough, someone scoops ice on the bodies of seven shivering students from Radboud University in Nijmegen (Netherlands). Are we witnessing a student baptism that gets out of hand?

No, it is an experiment designed by biomedical scientist Matthijs Kox of the Radboud University Medical Center (UMC). He is emailing us another photo. We see the same students bathing in a pool with ice cubes.

The experiment recently took place on the Wim Hof ​​estate. This Dutchman, better known as Iceman, who holds countless "cold records" to his name. For example, he climbed barefoot snowy mountains and stood for more than 70 minutes up to his chin in a container of ice cubes in the polar bear enclosure of a zoo. The mediagenic man draws strength from cold, breathing exercises and meditation. Through his training techniques, he could regulate his immune system and autonomic nervous system - something that is completely impossible according to the textbooks - and therefore withstand the most severe hardships.

‘When the Iceman approached us ten years ago to ask if we wanted to research him, we had serious doubts.’

"What Hof says goes against the prevailing scientific insights," says Kox. "When the Iceman approached us ten years ago to ask if we wanted to research him, we had serious doubts. I was very skeptical. But suppose he is right, that might offer prospects for the treatment of patients with inflammatory diseases such as rheumatism. For them, the immune system is overactive."

You have been researching the Iceman and his techniques for ten years now. He turned out to be right. How did you find out?

"In our research department, we gave Hof a harmless injection with a bacterial toxin to induce an immune response while he was doing his breathing exercises. Normally you will shiver, sweat and show all kinds of other flu symptoms for a few hours from that bacterial toxin. But Hof hardly bothered. There was a lot of adrenaline in his blood, which indicates an active autonomic nervous system. At the same time, blood levels indicated a remarkably mild activity of the immune system. "

Now you are working on new tests, with all those students in swimming trunks, to see which aspect of the Wim Hof method is exactly responsible for those super powers. Who knows, meditation is enough. That would be good news for rheumatism patients.

(Laughs) "Well, I don't think meditation plays a big role. In our last experiment we have ignored that. It was also only a small element of the training in earlier studies, and there is no evidence in the scientific literature that it could play a role. "

What exactly did you let the students do?

"Some were only exposed to cold, some only did breathing exercises and a third group did both. The training sessions lasted four days. We performed them on the Hof estate because we could use his swimming pool and practice hall. Hof did not interfere with the experiment. We have filled the pool with ice cubes for thousands of euros. The test subjects had to stay in that pool for as long as possible on day four. Some lasted for five minutes. They also had to lie in a container of snow for twenty minutes. For breathing exercises you had to breathe in and out very forcefully thirty times in succession and then tighten all your muscles for ten seconds. Everyone received an injection of a bacterium toxin afterwards. Now we are analyzing the blood samples. "

And what can you conclude?

"It's too early to say anything about it."

Are you not afraid of the outcome? Adjusting your autonomic nervous system with bathing and breathing exercises, that sounds a bit surreal.

"We have set up the experiment well. So no, I'm not scared. We saw a clear effect in the research with the students of Hof. The chance that this was a fluke is small, according to our statistical analysis. "

How long does it take before rheumatism patients benefit from the findings?

'I do not dare to say that. Even after this third experiment a lot still needs to be investigated. We do not make unfounded statements about the Iceman techniques. There are already a lot of them. I only believe what has been shown in scientific studies. In our case: there is clearly a suppressive effect on the immune system under controlled conditions in healthy subjects. "

Matthijs Kox

  • born in 1982

  • works at the intensive care department of the Radboud university medical center

  • did his research on the interaction between the immune system and the autonomic nervous system

  • has been reviewing the Iceman and his techniques for ten years and is leading a team of ten PhD students and technician

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