Our body can withstand a blow: ‘But we shouldn’t stay at 20 degrees all day long’ | Lelystad

While temperatures dropped rapidly over the past week, Wouter van Marken Lichtenbelt, professor of thermoregulation at Maastricht University, published a book about the science behind body temperature.

Although the thermometer in Amsterdam showed two degrees last Friday, it already felt much colder. In Winterswijk people were preparing for the first skating competitions on natural ice, while in Twente code yellow was in effect due to the snow nuisance. November 2023 went down as a mild month, with an average temperature of 7.8 degrees, but with an ice-cold finish.

“It was also a bit of a shiver for me, taking the first steps in the cold,” laughs professor of thermoregulation at Maastricht University Wouter van Marken Lichtenbelt. “Initially the body has to get used to adapting to cold. After a few days of cold it becomes more bearable, I hear myself say. Our laboratory tests also show this.”

“Two PhD students, Adam Sellers and Sten van Beek, are currently working on a first cold test with shivering, a series of ten days. It seems like everything is slowing down a bit. First the blood pressure increases, but after ten days it decreases and the blood sugars also decrease, after consuming a sugar drink. This also applied to fasting fatty acids and fats in the blood, which decreased. I call all these beneficial metabolic changes. That’s why my advice is: go out into the cold.”

November was mild and suddenly the sometimes biting cold set in. What exactly happens in your body?

“At extremely low temperatures you will shiver. This increases your metabolism, which is almost synonymous with body heat production, considerably, three to five times more than your resting metabolism. Then you can handle a lot, although shivering is not that comfortable. And again: after getting used to the cold, shivering decreases somewhat and the chemical heat production in our cells increases somewhat.”

From code yellow to snow. The weather in the Netherlands is becoming more extreme. How can we deal with this in a good way?

“We have gradually, over the past decades, slipped into a trap of comfort. Our bodies can take a beating, but we shouldn’t be stuck at 20 degrees all day. More effort in combination with more variation in ambient temperature works well, makes you more resilient to extremes – both cold and heat – and is healthy too. Moreover, we use less heating in the winter and less air conditioning in the summer. Energy savings are crucial to slowing climate change. I see this as killing two birds with one stone.”

Under what circumstances do you thrive best and what does that have to do with?

“I sometimes call myself a heat lover. I love warmth and it can also be nice and warm in my bedroom in the summer. But if I want to cycle a long way, I prefer a winter day again. I feel much more comfortable when exercising in the cold. And, strangely enough, I also enjoy wrapping up in a cold room in the winter. When I hear myself talking like that, I’m not very consistent.”

You have been researching this topic for over thirty years, but From shivering to sweating is your first book. Have you come across any notable discoveries while writing?

“A lot, in fact. For example, I delved more into the theme of ‘sports and temperature’. Then you notice that many things are recommended in the sports world for which the scientific substantiation is inadequate.”

Can you give an example?

“Many people cool their muscles after exercise in the hope that this will promote muscle building. Research suggests the opposite. You may promote recovery, but muscle growth will deteriorate. By the way, additional heating afterwards does not help with muscle growth. So it seems that the body itself is already doing it exactly right.”

Wouter van Marken Lichtenbelt: ‘Mild cold habituation – six hours a day at about 15 degrees – is positive for your metabolism and your sugar balance.’ © Getty Images/iStockphoto

To stay with the sport; Here in Amsterdam, despite the low temperatures, you see more and more people swimming in open water all year round. Is that good for you?

“If we don’t take the heart patients with us for a while, because they just have to be careful, then I say: yes, but with one condition. If swimming makes you happy, then that is positive and you should definitely do it. Our research has also shown that mild cold habituation – six hours a day at approximately 15 degrees – is positive for your metabolism and your sugar balance. So it is beneficial for the way your body processes food to be regularly in the cold.”

In the field of cold, you have initiated a number of research projects in recent years that were not only scientifically very innovative but also with clear social relevance.

“That is correct and in that context our cold research in people with diabetes and overweight people is worth mentioning. In both groups we saw a beneficial effect on their sugar balance. Their insulin sensitivity increased significantly and glucose uptake in the muscles improved.”

Your colleague Erik Scherder recently expressed the hope in this newspaper ‘that it will finally stop raining‘. In addition to shivering and sweating, do you also understand endless rainfall?

“The only advantage of the lots of rain is that our nature reserves are recovering from a few too dry summers. That makes me feel good. Furthermore, it makes me a bit sad every day when it rains. I lived in the tropics for a while and for five years I woke up in Curaçao with a pleasant surprise because the sun was shining. Yet I recently found myself feeling quite cheerful after a heavy downpour. Because something really happened. Even now I am not completely consistent.”

With the cooperation of Sebastiaan van de Water.

Wouter van Marken Lichtenbelt.
Wouter van Marken Lichtenbelt. © –

Wouter van Marken Lichtenbelt

Wouter van Marken Lichtenbelt (Zeist, 1965) obtained his PhD from the University of Groningen in 1991 on iguana research. He left for Maastricht University to study temperature and the human body. His pioneering work in the field of brown adipose tissue earned him international recognition in 2009. Since 2014, he has been a professor of thermoregulation and thermoregulation in Maastricht From shivering to sweating is his debut as a writer.

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Wouter van Marken Lichtenbelt

From shivering to sweating. The science behind body temperature of humans and animals
Veen Media, €24.99.