February may be the very hardest month in which to exercise: the good intentions of January are starting to wane and summer still feels a long time away. But you can no longer use the cold as an excuse. 'Is it ever too cold?' asks Dr John Castellani, an exercise physiologist at the US Army Research Institute of Environmental Medicine. 'The answer is no. People go to the poles, people are out there when it's minus 50 degrees, people do incredible things, and safely.' The key is doing it right - and that applies to jogging around the city as well as ice climbing in the Andes. Just remember: more people are injured from exercising in the heat than in the cold.
Before you go out
Check the conditions
Wet and windy weather affects how cold your body gets. Wind-chill factor increases with motion - important in sports such as cycling or skiing.
Wear the right clothes
Correct clothing depends on the sport and conditions, but, as a rule, try to stay dry - both from rain and sweat. Wet clothing loses 90 per cent of its insulating properties. Gloves, and a hat over your ears, will protect your extremities, which are more susceptible to cold. Make sure your waterproof is light and breathable. For your innermost layer, choose a light synthetic such as polypropylene, as cotton can become saturated and stay wet.
Don't wear too much
A common mistake is to put on excessive clothing. You should feel cool rather than comfortable before you start.
During exercise
Be aware of your body
Watch for early signs of frostbite and hypothermia, such as tingling, or burning skin and involuntary shivering.
Be careful when you take breaks
The trick to avoiding hypothermia is to keep moving (worth remembering when you are stuck in goal for half an hour). Plus, in the cold your muscles seize up more quickly, risking sprains.
Carry an energy bar
Exercising in the cold - particularly in heavy clothing - uses up more energy, up to twice as much on wet or snow-covered surfaces. Take an energy bar, especially if exercising for more than 90 minutes.
After exercise
Move to a warm environment
And change into dry clothes as soon as possible. Once you stop exercising your body heat will drop quickly. Don't go for the ice bath, but do wait a short while before taking a hot bath: allow your heart rate to drop first. A good way to reduce it is to stretch post-exercise. This may also reduce the chance of muscle strains.
Don't forget to rehydrate
When the body is cold, it draws blood away from its surface into its core. Research has shown that this masks the increased levels of salt in the blood that normally trigger thirst. As a result, we are less likely to want to take on fluids when exercising in the cold. Drink to satisfy your thirst and then drink some more.
