11 December, 2009

Training And Racing In The Cold

The past few days, here in Whistler, have been pretty darn cold.  The coastal humid air just made the cold feel even colder, however the temperatures are rising, and training is getting more comfortable.  I set out just like any other day, skinning up from the valley, and out into the alpine.  Doing intervals at just below my LT, which helped warm me up, I started thinking about how the body works in the cold.  And to make things harder, it was night time.

When your training in cold conditions, it's important to be warm, even going up.  If your warm, but not overheating, your less likely to burn off glycogen stores as quickly and go longer.  In the cold, if you begin shivering that can empty your glycogen stores 5-6 times faster than usual.  That being said, although your not usually shivering when skinning uphill, if you under dress this will cause a faster emptying of your glycogen stores.  To add to this, while in cold weather you may have an increase in epinephrine (adrenalin) levels in your blood stream, a hormone which will stimulate glycogen breakdown.

Now although your glycogen stores may be depleting at a faster rate, the body balances this with a higher rate of fat metabolism, using fat as fuel.  Higher epinephrine levels in the blood may also enhance fat metabolism.  There is some evidence that, during the winter and training in the cold, the body has lower insulin levels which could motivate fat breakdown.  The cold will also raise your resting metabolic rate, which will help improve body composition, and make you faster for racing.   With all this fat burning the big plus of training in the cold, you may begin to burn deeper internal fat which can be dangerous to your health.   This deep internal fat, is the fat that can be clinging to your organs, or be in your blood stream.  These bad fats are the fats which are noted to raise the risk of coronary artery disease.  The less these fats are in your blood stream, and body, the faster you will be (and healthier).

Studies have shown that at 5 degree Celsius marathon runners ran their best time, opposed to the 1.7% drop of when racing at around 1 degree Celsius, and a times dropping off even more in the heat.  So controlling your body temperature, and ensuring that you are wearing the right layering under your race suit or training clothing, you will be performing at an optimum level.  Racing, and training, with warm clothing but not enough to overheat will yield the best results.  On speed traverses, or multi-day tours, where you have to sleep out it is important to be light, but not overly light as you will shiver and deplete the next days glycogen stores.  If this happens you will start your next day in an energy debt, causing a massive drop in performance.  (photo above: Ty Petrusic prepares for a cold night after hammering all day)

The verdict?  Train and race with warm enough clothing that won't make you overheat.  Watch your calorie intake, to make sure you don't go into negative energy balance, while you may be burning more fat than usual.  Hydrate properly, your body will need more liquid during cooler temps.  And last but not least, don't let the cold stop you from training, as it may help you in the end.


  1. I find myself to slow down when back of my neck (or my whole neck) is getting cold, mostly due to windy conditions. So now I use a jacket that has a super high collar when I zip it up. Or when racing I would wear a bandana around my neck.

  2. Yeah I think keeping your throat warm is important. Burning your lungs with cold air, definitely slows you down, and that can help a bit. That is a great idea for racing though, I will have to try that at the Sunshine 5000.