Fresh, Small-Batch Nutrition for Better Health & Performance

Fueling for Warmth


By Jen Kates, CHC, CPT

We hate to admit it, but winter is here. If you want to get outside this time of year, you'll likely be faced with cooler, if not downright frigid, conditions. On these cold days it can be difficult to avoid feeling chilled while training outdoors.

While dressing properly is obviously critical, and the subject of another article, nutritional fueling plays a big role in maintaining body temperature in cold environments. Under-fueling can be a big contributor to struggling to stay warm while training in the cold.

As an athlete, you’re doing yourself a disservice by not fueling enough, even if your goal is to get leaner. By under-fueling, you’re not only impacting your performance, but also risking your body responding to the colder environment in a less-than-ideal manner. You may even find yourself feeling colder or having more difficulty warming up as you venture outdoors when the temperature drops.

This happens in part because the body requires more fuel to stay warm. In order to create heat, your body needs fuel in the form of food. As the temperature dips, the environment demands more energy for you to get and stay warm - and energy in the form of calories can help fill this demand.

Think about what often happens when you get cold: you may move more side to side to warm-up subconsciously, or your muscles shiver. Shivering is the body’s natural way to stay warm through tiny muscle contractions, because flexing muscles can generate heat. It’s estimated that shivering alone can burn up to 400 calories per hour, and that’s without being active in your sport.

Another nutritional mistake common with athletes during the winter is under-hydrating. The cold weather blunts your thirst mechanism, so you won’t feel as thirsty when you’re active outside. This happens despite sweating and losing water through your breath. More water is lost through your breath than you may think; when you breath in cold and dry air, your body attempts to warm it. In the process of exhaling, you lose a significant amount of water as the warm and humidified air leaves your body. Don’t skip your hydration - make sure that you stay hydrated by drinking a few sips of water every 15 or so minutes while you’re active. 

To make food and drinks more appealing during the colder weather, opt to consume warmer things in weatherproof or insulated containers. Drink things such as warm broths. Broths have sodium, which helps replenish some of the lost electrolytes through your sweating and breathing. Other warm things like apple cider and hot cocoa are additional drink options. 

For food, soups, stews, pasta (yes, noodles!), chilis, and potatoes can help keep you warm and give you the sustenance needed to stay warmer while outside in the cold. Another obvious snack option includes Enduro Bites, because they don’t get hard or freeze like other bars on the market, so they’re safe to carry in your jersey pocket in wintry conditions. 

How much should you eat and drink?

In order to determine how much food you should drink every hour, take a look at your wearable device, such as your Apple Watch or Garmin. See how many calories you burn on average every hour of activity when you’re outdoors. Then take roughly 50% of that amount and try to consume it via food and beverage. 

This is just a starting point, though, because leaner or more muscular individuals may require a bit more calories than others. So, in the process of experimenting, take note of your digestion, energy levels, and how well you sleep that night. If you have difficulty sleeping, don’t feel well-recovered for your next training session, or your hunger increases further the next day or two, then you may require a bit more calories per hour of activity. The goal here is to focus on eating every 45-90 minutes at a minimum while active as this helps prevent bonking or feeling like you are absolutely depleted.

For every hour of activity, you should also aim to drink at least 10-16 ounces of water or an electrolyte mix. Again, experiment with this amount and see if it works for you, but aim to take a few sips every 15 minutes or so.

Even if your goal is to shed a bit of extra body fat this season, you still need to make sure that you’re fueling enough in order to support your training. Ideally, males need at least 2,000-3,000 (or more) calories per day while females may need 2,000-2,500 (or more) calories per day to support their body’s basic functions (breathing, sitting, eating, and just living) in addition to their other metabolic demands on top of their training. 

By eating, and drinking, ample calories in your everyday life, in addition to every hour of activity, you are supporting your outdoor endeavors and training, while also helping yourself stay warm. Keep in mind that it may take some practice to figure out exactly how many calories you may need, but experimenting is half the fun. Just be sure to take note of how your energy, recovery, sleep, mood, and performance are as you experiment. If any of these things feel too low, then you may need to adjust your food intake a bit higher (say around 100-300 calories at a time, for 2-4 weeks at a time) before assessing how you feel.

Try implementing some of these tips and see how they may impact your training and performance overall. Share in a comment below about what works for you. 

About Jen Kates, CHC, NASM-CPT, Pn2, PPSC

Jen has been coaching for over 12 years and founded Shift Human Performance after working in the biotech research industry for 12 years. She specializes in coaching busy working professionals (like you) on how to unleash your full potential by optimizing your nutrition, fitness, sleep, and recovery, without spending countless hours in the kitchen or the gym. Besides her experience coaching hundreds of athletes, she holds several world-class certifications in personal training, health coaching, nutrition, and training pain-free.


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