Winter Fueling Tips
Even when the sweat isn't dripping, chilly weather is a prime time to focus on what's in your water bottle and in your belly.
The Basics
1️⃣Blood vessels can clamp down to help keep warm blood at the core, we might shiver to increase our metabolic rate, and for some, after consistent exposure to the cold an increase in the core temp during exercise or an input of heat into the core can cause blood flow to increase to the extremities despite the cold. These responses, however, do little to actually keep us from losing body heat.
2️⃣When we exercise in the cold, we might create extra heat, but the sweat, movement, and an increased ventilation rate can create some problems. One of those problems is the loss of more heat and the risk of getting too cold once we stop exercising because of excess moisture from sweat.
3️⃣That extra heat from exercise and the ease at which we can lose that heat in the cold puts strain on fuel stores. When exercising in the cold, we preferentially rely on carbohydrate (stored glycogen). A lot of that is due to an increase in our fight or flight response – activation sympathetic nervous system that works in the background to keep us charging under stress. Cold as a basic stress causes our sympathetic nervous system to light up which can cause us to waste precious energy, especially carbohydrate, making it a lot easier to bonk. Once we run out of carbohydrate, we risk becoming hypoglycemic. While becoming hypoglycemic is bad enough, becoming hypoglycemic and hypothermic can be even worse.
4️⃣This increase in sympathetic can also result in something known as cold diuresis. Essentially, when we’re cold or exposed to the cold we pee a lot.
5️⃣Cold air is extremely dry air, which can damage our delicate lungs which function best when the air we breathe is brought up to 100% humidity and to body temperature. As the temps drop, we lose more water and heat through our lungs to humidify and heat the air we breathe.
For further info and science keep reading here.
1. Be thoughtful in the fuel you pack and what you consume prior.
Fuel well before you head out. Bring a thermos with a warm beverage (if it has Skratch Hydration Mix even better!). It will help keep you fueled and warm.
2. Mix it up!
Bring simple sugars, carbs, a protein, sweet + savory. This will help ensure you so not get flavor fatigue and you can get the quick energy you need.
3. Squirrel it away.
Store your snacks close to use your body to keep them warm and from freezing. Keep your liquids insulated as well... avoid having your water turn into an ice block!
4. Stay on top of your snacking.
Set reminders. Aim a sip and/or snack every 15-20 minutes. It is much harder to bounce back once you already bonking. And when you are bonking you likely won't make great decisions. Your automatic thirst mechanism is depressed, meaning you feel less
thirsty even if you should be MORE thirsty.
6. Get warm before getting out!
Your blood vessels are less inclined to clamp down, which will help prevent cold hands + feet!
For more on the topic, check out the references below:
Gibson, J. C., Stuart-Hill, L. A., Pethick, W., & Gaul, C. A. (2012). Hydration status and fluid and sodium balance in elite Canadian junior women’s soccer players in a cool environment. Appl Physiol Nutr Metab, 37(5), 931-937.
Hailes, W. S., Cuddy, J. S., Slivka, D. S., Hansen, K., & Ruby, B. C. (2012). Water turnover and core temperature on Mount Rainier. Wilderness Environ Med, 23(3), 255-259.
Kippelen, P., Fitch, K. D., Anderson, S. D., Bougault, V., Boulet, L. P., Rundell, K. W. et al. (2012). Respiratory health of elite athletes - preventing airway injury: a critical review. Br J Sports Med, 46(7), 471-476.
Marek, E., Volke, J., Muckenhoff, K., Platen, P., & Marek, W. (2013). Exercise in cold air and hydrogen peroxide release in exhaled breath condensate. Adv Exp Med Biol, 756, 169-177.
McMahon, J. A., & Howe, A. (2012). Cold weather issues in sideline and event management. Curr Sports Med Rep, 11(3), 135-141.
Sue-Chu, M. (2012). Winter sports athletes: long-term effects of cold air exposure. Br J Sports Med,46(6), 397-401.
Yoshida, T., Takanishi, T., Nakai, S., Yorimoto, A., & Morimoto, T. (2002). The critical level of water deficit causing a decrease in human exercise performance: a practical field study. Eur J Appl Physiol,87(6), 529-534.
(2011). Update: cold weather injuries, U.S. Armed Forces, July 2006-June 2011. MSMR, 18(10), 14-18.