When the temperature starts to dip and snow covers the street, even the most hard core runners may have a hard time getting up the enthusiasm to layer up and go for a run. And staying hydrated might be the last thing on your mind. Sure, it’s easier to remember to drink enough water and carry enough water when it’s eighty degrees out. But in the winter your body can be tricked into thinking you don’t really need to drink that much. The cool air and snow can mask our sense of exactly how much fluid we’re really losing. And that can lead to dangerous dehydration. So runners need to hydrate in the winter.
It’s not unheard of that up to 8% of total body mass has been lost through the loss of fluid in runners in the winter. This is made worse by the fact that most runners wear multiple layers of clothes on a winter run. You are still sweating, and that fluid needs to be replaced. Dehydration puts stress on your cardiovascular system.The kidneys will begin to produce more urine, which can lead to more dehydration. Also, your lungs have to work harder to moisten the cold winter air as you exhale. So water is being exhaled every time you breathe.
An extra problem with running in cold weather is that dehydration can lead to frostbite. Your body will try to compensate for the cold by attempting to keep more warm blood in your core as opposed to your extremities. This is why shivering is one thing the body does to generate heat.
The American College of Sports Medicine recommends drinking up to sixteen ounces of water prior to exercise and several sips every few minutes during exercise. If you’ll be running in the cold, you can make some of that fluid intake a hot drink such as tea or hot chocolate to help warm up your core before heading out. And make sure you wear enough layers to protect you from the elements, but not too many.