Winter Hydration

I've been noticing a lack of hydration and a lack of concern for hydration this winter. Summer runners usually head out the door decked out with fuel belts and hand held water bottles full of sports drinks, gels, and electrolyte tablets. Winter runners seem to be empty handed. Many athletes report not being as thirsty in the winter assuming their hydration needs are less important. But is this true?

Winter exercise actually poses many challenges, albeit different challenges, compared to warm weather working out. Breathing in cold, dry air increases water loss as the lungs have to work harder to warm and humidify air. Sweat evaporates more quickly in the dry air so athletes don’t always realize how much they are actually sweating. Metabolic rates and therefore water losses increase in order to keep core body temperature up. Warm clothing may actually cause more sweat than in summer months with poor wicking capability. In cold temperatures, the body produces more urine with a lower specific gravity, a phenomenon called cold-induced diuresis. Many winter sports take place at altitude which can even further increase water losses because of low humidity levels and hyperventilation.

Proper hydration helps maintain blood flow assisting in body temperature regulation. Maintaining a hydrated state can also help reduce compromised performance from as little as 2% dehydration. Therefore, we should remind our athletes to practice these basic hydration tips, especially when the temperature drops:

·        1-1.5 hours before exercise, drink a large amount of fluid (0.5 liters) to increase gastric emptying.

·        Continue to drink ½ cup every 10 minutes.

·        Dress in layers to avoid overheating. If possible, strip a layer after a 10-15 minute warm-up.

·        Urinate before running as a full bladder can increase water losses.

·        Aim to drink 20 ounces fluid every hour. If exercising for over 60-90 minutes, consider a carbohydrate and electrolyte containing beverage. To keep the cap of your water bottle from freezing, coat the tip in Vaseline.

·        Replace what you lose while running. Consider a winter sweat test or have athletes weigh before and after to gage accurately.

·        Recover with warm beverages like diluted apple cider, broth, decaf tea and hot chocolate milk to warm the hands and hydrate. Also consider hydrating with winter foods such as citrus fruits and soups.

References:

1.    Benardot, D. Advanced Sports Nutrition. Champaign, IL: Human Kinetics, 2006.

2.    Cold Weather Water Bottle Tips http://www.mazamas.org/your/adventure/nw/cold-weather-water-bottle-tips/

3.    Key Tips on Hydration in Winter http://www.europeanhydrationinstitute.org/key_tips_on_hydration_in_winter/

4.    Severe Hypothermia http://www.princeton.edu/~oa/safety/hypocold.shtml