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This article is featured in the Summer 2022 print issue of Trail Runner.
Gearing up for adventure runs in different climates and terrains requires a flexible nutrition tool kit to fuel you right, to ensure you aren’t left stranded and running on empty.
Often, runners have one fueling plan that they use for each longer effort, failing to adjust for the targeted adventure. With consideration, you can most likely take that tried-and-true plan and make it a winner, no matter what the day brings!
When your adventure will start and how long it will last should determine your pre-adventure fueling strategy.
Keep in mind that a pre-adventure meal has a dual purpose:
- Load up glycogen stores to get you ready for a longer effort, and
- Ensure you are well-hydrated.
When focusing on pre-adventure fueling, remember:
- Hydrate. If you are starting in the morning after a night of sleep, you will have naturally lost fluids through respiration. A good target for intake is about 16-20 oz of fluids before you start.
- Consider Electrolytes. Aim for one serving of electrolytes (250 – 500 mg.) in your flask or bladder to help retain the fluids you take in.
- Calories/Carbohydrates: The longer the proposed adventure, the higher the pre-adventure calorie target should be. A good starting place is about 500 calories for a two-to three-hour run. The rule of thumb is at least 1g/kg of bodyweight in carbohydrates pre-run. So, for a 140lb runner, that’s about 64g of carbohydrates (255 calories). The remaining calories should come from low-fiber carbs and protein. Some fat can be good (though too much can cause GI distress), so shoot for ~10g or less.
- Time it Right: If you are consuming a higher calorie meal, timing is essential. Aim for one to three hours before you leave, to minimize chances of gastrointestinal distress.
Fueling Differences for Longer Adventures
The longer the adventure, the more fuel you’ll need to carry. According to the American Council on Exercise, a 120lb person burns about 11 calories per minute while running. So, an average runner can easily expend 600-1,000 calories per hour depending on terrain, weather, body frame, and intensity. You should aim to replace around 30-40% of those, which breaks down to around 180-400 calories per hour.
Longer adventures tend to be a bit slower. Due to that lower intensity, you might be able to take in more calories, as blood is not diverted away from the GI system as much. This will require you to carry more fuel or become smarter with your fueling choices (aim for energy-efficient choices like gels and chews for a smaller volume of food).
Because of increased blood flow to the gastrointestinal system, the makeup of macronutrients in food choices can vary, too. At higher intensities, the body uses more carbohydrates. At lower intensities, the body can handle more fat and protein as fuel sources (cue the PBJ and pizza). That doesn’t mean to skip the carbs; it just means that you may need less. Minimum carbohydrate requirements per hour of exercise are about 30g.
Carrying Your Fuel
Having a plan for carrying your fuel is nearly as important as your nutrition plan itself. A traditional handheld bottle may not be your best bet if you are running longer than two hours, because storage can be a problem.
Some things to consider when planning how to carry your fuel:
- Pack extra. If you are using a hydration mix, take extra powder along with you.
- Do the math. Count your calories ahead of time. Take at least 250-500 calories of extra fuel with you, in case you get lost.
- Assess the weather. If adventuring in the cold, remember that gels and hydration can freeze. Try insulated bottles and food options that won’t freeze, like baked goods.
- Be salty. Consider carrying extra electrolytes like Base Performance Salts or Salt Stick Tabs in case it turns out to be hotter than expected.
- Filtration is key. Consider carrying a filter bottle like those made by Katdyn, Hydrapak, or Salomon. These contain a built-in filter and require no water purification tabs, so you can get water from streams if you need to.
- Bladders are key for longer outings. A hydration pack is going to be your best bet for long adventures, so that you can carry all of your fuel and gear. Be sure to choose one with enough room for all of your needs.
Altitude and Terrain Considerations:
If you are heading to higher elevations or mountainous terrain, you’ll want to prepare yourself nutritionally for the conditions. Running at higher altitudes causes physiological responses to be exaggerated. As a result, energy, fluid, and electrolyte requirements are higher.
Fluid loss increases due to increased respiration, lower humidity, and dry air, so you’ll need to take in more electrolytes. To make things even more challenging, thirst is typically reduced at higher altitudes, so relying on it is not a good strategy to meet your needs. It’s important to plan for increased fluid and electrolyte requirements.
Even if you have a baseline fueling plan dialed in for long runs or races, adventure runs may require a revised approach. Considerations should be taken for distance, altitude, and terrain of the proposed run. When in doubt, it is always best to be prepared with extra fuel, just in case you need to adapt.
From Summer 2022