Running in cold weather can lead to more than just the minor inconvenience of ruddy cheeks and chilly ears. So, take extra care when running in the rain or the snow. Slow your pace and stay relaxed and under control and watch out for wet leaves or icy patches. When it's cold outside, be extra rigorous in your warm up. Start by walking briskly, then progressing to a slow jog, before finally finding your normal pace.
There's something else to watch for too. Head out for a run in chilly temperatures - it doesn't even have to be sub-zero - inadequately dressed and you could be running the risk of hypothermia.
Although rare among runners, it is worth knowing what hypothermia is, how to spot it, and what to do to prevent it. It occurs when your body temperature drops below 35.5ºC and can be fatal if untreated. It's most likely to occur if you are soaked by a sudden downpour on a cold day. Wet skin loses 25 times more heat than dry flesh. Symptoms include shivering, a slow pulse, lethargy and a decrease in alertness. In severe cases, muscles become rigid and the victim can lose consciousness.
If you, or a training partner, show any signs of hypothermia, here's what to do: keep moving to generate heat; find a warm place, wrap yourself in blankets and drink warm liquids. Refuse the hot toddy you'll be offered as alcoholic beverages do not warm you. In fact, they cause more heat loss and promote fluid loss.
Runners who are most at risk are those who run in rural areas and on trails. Run with a partner, dress appropriately - see layering below - and carry a sports drink even on the coldest of days, as dehydration also makes you more prone to hypothermia.
The best way to avoid a serious chill is to dress properly. You're unlikely to head out into the elements dressed in little more than a thong, but you don't want to pile on as much kit as you can find either.
The key to cold-weather dressing is layering. Wearing three thin, synthetic layers rather than one thick top means you can regulate your body temperature by removing or adding items of clothing. Also, warm air becomes trapped between the layers. Here's how to get layered:
Base layer: Choose a thin, snug and breathable material that'll wick moisture away from your body. If sweat is trapped next to your skin, you'll find it much harder to keep warm. This will be adequate on it's own if the temperature stays above 5ºC.
Mid layer: This provides extra insulation by trapping warm air, but you'll usually only need it on particularly cold days - below freezing. Again, this layer needs to be breathable and wicking.
Outer layer: This is your protection against the elements. It's unlikely to become cold enough to wear all three layers in most parts of the UK, but if there's a gale howling or rain lashing down, opt for a wind-proof, water-resistant shell. Why? Because, when it's windy or you're wet, you'll lose body heat far more quickly than in still, dry conditions.
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