Hi there, I'm an avid runner and blogger who runs an endurance sports site, primarily focused on running and triathlon. While I'm not a nutritionist, I have plenty of experience with long runs in cold weather, so I hope you find my response helpful. Should you wish to use my comments in your article I would appreciate a backlink to my site - theordinaryathlete.com - from the article. If you have any additional questions feel free to let me know! Many thanks, Chanelle Rosenbaum Owner & Writer at The Ordinary Athlete Answer: My fueling protocol doesn't change much in cold weather, but my hydration strategy does. For long runs up to two hours, I usually carry a handheld bottle and take small, regular sips throughout the run, mainly to stay topped up and to wash down nutrition. For runs longer than two hours, I'll often plan one or two short stops at a cafe or corner store to grab a drink and warm up briefly before continuing. A hot tea or coffee can make a big difference when spending several hours outside in very cold conditions, and it's an easy way to increase fluid intake when thirst cues are low. For fueling, I typically aim for 30-50 g of carbohydrates per hour, depending on the duration and intensity of the run. I get this from a mix of gels and solid foods, such as bars or candy. While I don't visibly sweat as much as I do in warm weather, I still prioritize electrolytes and aim to take in sodium about every 30 minutes. In cold conditions, I find salt tabs or chews work best, as they don't require drinking large volumes of water and are easy to stay consistent with when it's cold.
Cold weather blunts thirst, so my rule is fuel and sip by schedule, not sensation. For long runs below 40degF, I set timers and stick to a simple target that keeps energy steady without GI issues. Carbs per hour: I start most runners at 30-45 g carbs/hour (one gel or chew every 30 minutes). If the run is >2 hours or includes pace work, I'll nudge toward 45-60 g/hour, split into smaller doses to keep digestion smooth in the cold. Sodium strategy: Even when sweat feels lower, sodium still matters. I aim for 400-600 mg sodium/hour. In practice, that's a lightly salted carb drink or water plus a salt capsule/chews. The cold can mask losses, but skipping sodium is how people end up flat, crampy, or lightheaded late. How we execute it (below 40degF): Pre-run: 12-16 oz fluid with ~300-500 mg sodium. During: Sip 3-5 oz every 15-20 minutes, regardless of thirst; carbs every 30 minutes. Form: Gels/chews work well in the cold; warm bottles if possible to encourage sipping. Proof with a client: A client training in the low 30s went from bonking at 90 minutes to finishing strong after moving to 40 g carbs + ~500 mg sodium/hour. Pace stabilized, perceived effort dropped, and post-run headaches disappeared. As a NASM Certified Nutrition Coach (CNC) and ISSA Nutritionist, I keep winter fueling boring and repeatable. Timers beat thirst in the cold.
For long runs in cold weather, hydration is crucial since thirst cues can diminish, risking underhydration and performance. Aim for 30-60 grams of carbohydrates per hour to maintain energy without gastrointestinal issues. For a 70 kg (154 lbs) runner burning 600-800 calories hourly, this carbohydrate intake is effective. Prioritize carb intake along with sodium management to optimize fueling and hydration during such runs.