Running in hot or cold weather in Quebec: adjusting hydration and carbohydrates

Few places require as much adaptation as Quebec: 30°C with the humidex in July, -20°C in January, and sometimes a 20-degree swing in the same week during spring. Your nutrition strategy cannot be the same all year round. Here is what to change.

What doesn't change: carbohydrates

Your carbohydrate needs depend primarily on the duration and intensity of the effort, not the temperature. Summer or winter, aim for 30 to 60 g per hour for a 75-minute to 2.5-hour session, and 60 to 90 g per hour beyond that. What does change is the amount of water and sodium, and how you carry everything.

In hot weather

Heat increases your sweat rate and diverts blood to the skin to cool you down. Your digestive system receives less, making your stomach more sensitive.

• Drink more, according to your thirst. Needs often rise to 600 ml or 1 liter per hour.
• Dilute your drink. Keep the same total amount of carbohydrates, but in more water: one serving per 500 ml rather than two.
• Increase sodium to around 500 to 800 mg per hour, or more if your sweat is very salty. Benchmarks are in our guide on sodium per hour.
• Start hydrated: about 500 ml in the two hours before the session.
• Keep your drink cool. Fill your bottle halfway the night before and put it in the freezer, then top it off before leaving.
• Slow down. In high heat, no nutrition strategy can compensate for a pace that is too fast.

Count on about ten days of training in the heat for your body to adapt. The first heat waves of June are always the hardest.

In cold weather

In winter, we sweat less, but we still dehydrate: dry air causes water loss through respiration, layers of clothing make you sweat, and the cold reduces the sensation of thirst.

• Drink even without thirst. A few sips every 15 to 20 minutes on a session lasting more than an hour.
• Do not cut carbohydrates. The body burns just as many, sometimes more if you are shivering or running in the snow.
• Concentrate your drink. Since you drink less, two servings per 500 ml provide the desired carbohydrates in a small volume.
• Sodium remains useful, but 300 to 500 mg per hour is generally enough.

Preventing your bottle from freezing

• Start with lukewarm or warm water.
• Carry your soft flask under your jacket, against your body, rather than in an outside pocket.
• Blow into the nozzle after each sip to send the liquid back into the bottle: the nozzle is what freezes first.
• A sugary and salty drink freezes a little slower than pure water.
• Below -15 °C, plan loops that pass back by the house or the car to change bottles.

Spring and autumn

Both seasons hold traps. The first hot day in April hits hard, because your body isn't adapted to it yet: treat it like a heat wave day. In the fall, race starts at 2 °C followed by a finish at 15 °C require a summer hydration plan with winter clothing.

Cheat sheet

These ranges are starting points to be adjusted according to your thirst and how you feel. One serving of ELIXYR Endurance Fuel contains 30 g of carbohydrates and 340 mg of sodium, which makes the dosage easy to adapt from one season to the next.