• Question: Why do we shiver when we are very cold?

    Asked by Mariah to Marikka, Matt, Rob on 19 Nov 2014.
    • Photo: Marikka Beecroft

      Marikka Beecroft answered on 19 Nov 2014:

      Your body needs to maintain a good 37°C to function properly. If it drops it could damage your organs or brain, so to stop this happening your body strictly regulates temperature.

      Your brain does this by monitoring your skin and body temperature and when it gets too cold it uses several ways to keep warm; one of them is shivering. When you shiver it’s actually your muscles squeezing and relaxing really quickly and this movement produces heat warming you up.

      A good example of this is walking or running on a cold day. When I was in secondary school our gym teacher was a bit… mean … and made us run in the snow in gym skirts. We were all freezing our butts off but after a while running around the fields we got warmer because our bodies muscles was heating up when we used them. Maybe you’ve experienced this too walking to school in the winter!

      Hope this answered your question! 🙂

    • Photo: Robert Hampson

      Robert Hampson answered on 20 Nov 2014:

      It is a automatic biological response to being cold. When your muscles contract, they use a lot of chemical energy. However, your muscles are not particularly efficient so a lot of the chemical energy also gets turned into heat. Therefore, when you are cold, your brain tells your muscles to do lots of little contractions to make your muscles keep your blood warm.

      Most people also automatically do things like rub their hands together. This generates friction between their hands generating heat thereby keeping their hands warm.

      Also, when you are cold, your hair often stands on end. This is an old evolutionary relic. When we were previously covered in longer fur, hair standing on end would trap a layer of warm air deep in the fur, keeping you warmer. However, since we have lost the fur our hair can no longer do this (except on our head), and we just get goosebumps!