What happens to heat when you sit still
Short answer: Muscle work is the body's source of heat. When you sit down, heat production falls to around the resting level, while heat loss carries on unchanged. That is why many people start to feel cold soon after sitting still, even though the clothes and the room are the same as before.
The muscles are the body's furnace
When you walk, lift or move about, your muscles work and give off heat. It is the biggest source of warmth through the day. As soon as you take a break, production drops, and the body misses the extra heat you got for free by moving around.
Production falls quickly
After a few minutes of rest, heat production is back to around one hundred watts. The heat you got from walking is gone at once. The body cannot store it for later, so you notice the difference almost immediately, in hands, feet and back.
The loss carries on
The clothing still insulates just as much, but that is not enough to cover the difference. So you begin to cool down even though you have changed nothing. A layer that was right on the move is too thin at rest. See for example a bamboo hoodie for men to pull on during a break.
Moisture makes it worse
If the clothes are damp from activity, the water now evaporates and draws extra heat from the body. Then you lose heat through the fabric and through evaporation. See bamboo sweatshirts for men and sleepwear if you want soft clothes to change into once you get home.
Hands and feet notice first
Hands and feet sit at the edges and have less muscle mass, so they often cool first when heat production falls. You can sit still with a body that is perfectly comfortable and still have cold fingers. An extra pair of socks or one more layer on the torso often helps more than you expect.
Quiet work and breaks
Desk work, car journeys and cinema visits have one thing in common: you sit still for a long time. Heat production stays low throughout, so a different choice of clothes suits than for a walk. Take an extra layer along that you can remove if the room turns out warm.
An extra layer before you freeze
It is easier to keep heat than to get it back. So put a layer on before you start to feel cold, not after. Once the body has lost a lot of heat, it takes longer to feel good again, even if you dress up and sit near a source of warmth.
Outdoors and indoors
When you go from outdoors to indoors, the situation changes fast. Outside you move, inside you sit. That can bring a sudden feeling of cold just after you come in and sit down. If it is too warm, take a layer off, and if it is too cold, put one on.
How to plan your day
Think about how much you move and how long you sit still. Choose layers you can take on and off. Bring something dry along if you expect to sweat. That way you are dressed for active spells and for breaks, and you avoid freezing when heat production falls.
Frequently asked questions
What should I do when I take a break?
Put an extra layer on at once, before you start to feel cold. It is easier to keep heat than to get it back once the body has lost a lot, and breaks are often shorter than you think.
Why is it worst after exercise?
Because production falls and evaporation from sweat peaks at the same time. The body loses heat from two sides at once, so it often feels colder after a workout than before, even though the room is the same.
How long does it take?
Often under ten minutes before you clearly feel the difference. The time depends on the clothing, the room temperature and how damp the clothes are, so the first stretch after activity is when it pays to pay attention.
You can find the full range at Bamboo-Clothing.com.
