Be prepared for when the frost bites
The skin’s surface, peripheral muscles and limbs are the first areas to go cold when you get chilled, so this is usually where you will notice any kind of reaction to falling temperatures. ‘The arteries and veins vasoconstrict,’ says Neale Tillin lecturer in exercise physiology at the University of Roehampton. ‘This means their diameters get smaller, so there’s less room for the blood to move through them as heat is lost through veins and arteries.’ You may notice your hands and feet turn white, or have a blueish tinge because there’s less blood (which gives skin its pinkish colour) near the skin’s surface. When you feel chilly, you may also start shivering. This is basically an involuntary contraction of your muscles. ‘For the muscles to contract, your body needs to increase its metabolic rate, which is the speed at which chemical reactions occur,’ says Tillin. ‘These reactions then produce heat to warm up the body.’ Often your skin will also be covered in tiny bumps, known as goose bumps. ‘Some believe this is a leftover from evolution when we were a lot hairier and didn’t wear clothes,’ says Tillin. ‘The bumps are the hair follicles on the skin forcing the hair to stand up right. When this happens, the hair traps air close to the skin which can form a protective layer.’ Internally, the hypothalamus signals to the adrenal glands, which release hormones such as adrenaline. These raise the metabolic rate to produce warmth, while other hormones activate the production of thyroid hormones, which also produce heat.
”TALL, SLENDER PEOPLE FEEL THE COLD MORE”