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  • Mareli Ochs

Chill Factor

With millions of followers, Dutch extreme athlete Wim Hof, aka The Iceman, is leading a revolution in health and wellbeing that scientists are just beginning to comprehend. Everything from lowered stress levels to improved immune function is promised, if we can only learn to chill. By Mareli Ochs
"The Iceman", Wim Hof, painted by Daniel Butterworth.

The sun has not yet risen on Sydney’s Bondi Beach as a group sits rugged-up on the sand, breathing to the rhythmic shush of the ocean. It is 11 degrees Celsius and yet soon they will strip down and submerge their bodies in the ice-filled blue portable baths that are lined up to their left.

More than 16,600 kilometres away, as the crow flies, is the man who created the technique they and countless others around the world are practising.

Dutch extreme athlete Wim Hof always wanted to change the world.

In March, speaking at the inaugural Human Kind summit at Sydney’s Luna Park, Hof recalled, as a 12-year-old boy, feeling saddened by the sickness he saw around him, the Vietnam War, abuse and pollution. It was 1972, and Hof told himself he didn’t know how he would do it but he would somehow help relieve people’s suffering. Five years later he would feel the invigorating effects of the cold for the first time — jumping into an icy canal in Amsterdam on a whim — and begin a journey that would change his life, and eventually the lives of others.

At the age of 40, Hof set the Guinness World Record for the farthest swim under ice; at 57 metres, it was more than the length of an Olympic swimming pool. At 47, he climbed within 1,400 metres of Everest’s summit in just shorts and shoes. The same year, he set another Guinness World Record for the fastest half marathon completed barefoot in snow (two hours and 16 minutes). And at the age of 50, the father of five set the then-record for enduring the longest direct full-body contact with ice. Such feats have earned him the moniker “The Iceman”.

As he paced the Human Kind stage, barefoot in shorts and a tie-dye T-shirt, Hof said, “I am sort of an anomaly. I’m a bit strange, crazy.” Out of his strangeness emerged a method for adapting to stressors and cultivating fearlessness by consciously calming his body. Through a breathing technique that involved hyperventilation and breath retention, Hof showed he could tap into the autonomic nervous system to change the body’s response when it was faced with a stressor, such as extreme cold. Confoundingly, as he demonstrated in one experiment, this, in turn, reduced the reaction to endotoxins that activate the body’s inflammatory response.

Hof on stage at the Human Kind summit in Sydney in March. Photography courtesy of Human Kind.

It is perhaps ironic that a man of such extremes has become a poster child for those seeking balance. Or perhaps it is not. Some research suggests about half the global adult population feels chronically stressed, which aligns with Australian research looking at the stress levels of 25–54-year-olds. While we can’t always change the stressors we face, Hof’s method promises a way to adapt our physiological and psychological responses to them. “We are able to alter the immune system and bring down what makes us into disease — inflammation,” says Hof. “To reset us to the way nature meant us to be — and that is where there is no disease, no darkness of depression ... you are in charge.”

Some experts question Hof’s understanding of physiology. Hof has suggested, for instance, that humans tend to overthink, and that all that overthinking means other parts of the brain — the limbic system and the deep brain — get less blood flow. Through cold showers, he says, we can invigorate our deep brain with blood flow. Says Professor Bryce Vissel, a neuroscientist based at St Vincent’s Hospital Sydney: “Cold showers can feel invigorating, but science has not answered the neurological basis of why that is the case. Hof invokes concepts that ... would not be supported by our understanding of the brain.” However, notes Professor Vissel, we don’t always need to justify why some activities can feel beneficial to try them, providing they do no harm. “If it makes you feel good and you are healthy, I’d say go for it, with two caveats: it is not a substitute for medical therapy for serious disease and it may not be safe for some people, for example [those] with heart conditions.”

Indeed, there is some evidence that versions of Hof’s method may assist in managing stress or can help as a recovery tool. The few studies that examine the method (or versions thereof) suggest it can reduce stress levels and inflammation and relieve depressive symptoms, and that we can wilfully regulate our body’s temperature and activate hormonal changes that inhibit our response to pain.

Submersion in ice baths. Photography by Joseph Mayers.

Meanwhile, cold therapy alone may be sufficient to improve metabolism and thermoregulation, which allows organs and bodily processes to work effectively. It may also be an effective recovery technique that works by reducing muscle inflammation and speeding up recovery.

One exercise physiologist I speak with, whose research has looked at the effects of cold therapy after intense exercise among elite athletes, says that submersion in cold water is more effective than a shower for recovery. This is due to the completeness of contact between the body and the water, which provides a better stimulus. It also increases pressure on the limbs, especially the legs and feet, which enhances the effect. For recovery, she says spending 10 to 20 minutes in a bath no colder than 15 degrees Celsius will do the trick.

And although gains in muscle hypertrophy may be blunted if you have a cold bath too soon after exercise (within four to six hours), endurance gains won’t be lost. If the goal is just to energise yourself, a 30-second blast of cold at the end of your hot shower is likely to be enough. It might even reduce the likelihood of you getting sick, according to one study of more than 3,000 people, which found blasts of cold longer than 30 seconds were no more effective.

While the cold might give us a boost, breathing exercises may have the power to bring us back down from states of heightened anxiety.

Hof has trained himself to be comfortable in fearsomely low temperatures.

Through controlled breathing, we can start to train our body and brain’s response to stress. By consciously slowing our breath, for instance, we signal the autonomic nervous system, which controls our heart rate, blood pressure, digestion and sexual arousal. When we are stressed and our sympathetic nervous system is driving, our digestion and ability to be aroused are shut down while our heart rate and blood pressure spike to help us tackle whatever threat is making us feel uneasy.

The manipulation of our breath, however, can put the parasympathetic arm of our nervous system back in control. That leads to a slower heart rate and lowering of blood pressure while our digestion and ability to be aroused are reactivated. This has knock-on effects for our mood and stress levels.

In one study by researchers at Stanford University, published in January, participants practised one of three forms of breathing: cyclic sighing (prolonged exhalations), box breathing (equal duration of inhalations, breath retentions and exhalations) or cyclic hyperventilation (longer inhalations, shorter exhalations). The study found that five minutes of breath work a day, in any of these forms, led to improved mood and reduced anxiety and stress. The greatest benefit, however, came from cyclic sighing.

A separate study led by the UK’s University of Sussex, published in the journal Nature earlier this year, found that slowing our breath can also change our brain’s electrical activity, enabling diverse brain regions to communicate more effectively. This may help us to better manage and adapt to stressful situations. And by bringing down our stress levels — and therefore the chronic release of stress hormones, along with our heart rate and blood pressure — it is possible to reduce inflammation in the body.

Audience members trying Hof’s breathing method. Photography by Joseph Mayers.

Experts warn that Hof’s method should not be practised alone — because of the risk of fainting — or if you have a respiratory condition, anxiety, high or low blood pressure, or are pregnant. Hof’s method involves three parts: several rounds of forceful breath or hyperventilation followed by holding the breath, followed by deep inhalations and exhalations; exposure to cold; and mindful body-awareness focus on deep breathing. By strongly breathing out, we expel more carbon dioxide, creating a temporary state of alkalosis. This means when we then hold our breath, it takes longer for carbon dioxide, which creates the urge to take a breath, to build back up. The technique also stimulates adrenaline, followed by the increased production of anti-inflammatory molecules which may allow our body to respond better to illness.

During the breath retention, with large amounts of adrenaline circulating through our bodies, we also have to remain calm. This can help us manage stress, whether it is caused by cold water or otherwise. This, combined with the energising effects of the cold, can leave us feeling elated and better able to tackle the day. It can also help us to understand why people might be willing to brave an ice bath on a dark and cold Bondi morning.

A survey led by RMIT University of more than 3,000 people around the world found that those who practised Hof’s method experienced feeling more energy and focus, and less stress and anxiety. In a separate study, researchers scanned Hof’s brain before and after practising his method while being exposed to cold designed to create mild hypothermia. The scans showed that his method enabled him to activate a stress-induced pain-relieving response in the brain. He was also able to activate parts of the brain that are uniquely associated with self-reflection, and which facilitate both internal focus and sustained attention in the presence of stressful stimuli, the researchers said.

The conclusion was that there’s a “compelling possibility” that Hof’s method might allow practitioners to develop a “higher level of control over key components of the autonomous system”. This could, the researchers said, become a lifestyle intervention that might ameliorate multiple clinical syndromes.

Hof has come to realise that maybe he is not such an anomaly after all: he is not the only one who can consciously influence their autonomic nervous system to change the way they feel and the way their body responds to stress: we all can.

Just maybe, in the end, it is also about our mindset, which all sports professionals know comes from pushing ourselves beyond our comfort zones. As Hof finishes his session at Human Kind, he calls to the crowd: “Let’s say this together: ‘We can change the world.’ ”

And they all call back.

Follow the expert health guidance if attempting any of the practices described.

This is an extract from an article that appears in print in our eight edition, Page 16 of Winning Magazine with the headline: “Chill Factor”. Subscribe to Winning Magazine today.


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