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“I feel drunk!” My words slurred and vision blurred as I stumbled on day two of my first-ever, multi-day trail run—traversing the Sierra Nevada Range from east to west (and back), totaling 50 miles. Despite knowing that I needed significant amounts of calories and fluids to power me over the 12,000-foot Mono Pass, I figured that a few Pop Tarts, bags of jellybeans and water would suffice. The result was the worst bonk of my life deep in the wilderness.

The adage that if the furnace is hot enough it will burn anything may be true, but when the fire is stoked over 24 hours it burns differently, and it becomes significantly harder to carry the logs (aka fuel). While multi-day trail endeavors vary greatly—from FKT attempts to stage races like TransRockies, from challenging 100-milers such as Hardrock 100 to recreational fastpacking—several key fueling considerations remain the same.

Carbs Are King

According to Kristen Chang, MS, RDN, CSSD (a trail runner who works with ultramarathoners on diet plans), “Similar to ultramarathons, the major fueling goals for multi-day trail runs and races are to minimize the energy gap between intake and expenditure, consume adequate levels of micronutrients and prevent over or under hydration.”

She acknowledges the additional challenges: “Fueling for a multi-day event is complex in that runners have high energy needs and yet often have difficulty meeting those needs due to factors such as loss of appetite, flavor fatigue and limitations in carrying capacity.”

Regardless of duration, carbohydrates remain the primary fuel source for endurance events. “To meet carbohydrate needs during multi-day running,” says Chang,  “aim for a mixture of carb sources including gels, sports drinks and regular foods.”

Limiting fat and fiber is essential as these nutrients increase risk of gastrointestinal issues, which can hinder the ability to fuel consistently and keep up with energy demands.

Not all carbohydrates are created equal, though. “Focus on carbs that are lower in water, protein and fiber and higher in glycemic index (readily absorbed into the bloodstream) like white rice, bagels, pretzels, cereals, granola bars and dried fruit.”

In addition, fat can be processed by the body as fuel at lower intensities, and pack more calories in a lighter package, which is a critical component of self-supported missions (think nut-butter travel packs like NuttZo 2Go packets). Protein remains a relatively small requirement (10 percent) of the body’s energy needs during multi-day runs, but ingesting a quality protein source immediately following activity boosts recovery for the next day of running. Aim for 20 to 30 grams of protein like chocolate milk or whey protein mixed with tart cherry juice (to help reduce inflammation).

Drink mixes can also provide efficient carbohydrates and calories. Accomplished mountain runner Luke Nelson, 37, of Pocatello, Idaho, utilized a fluid-focused regimen during his FKT record for linking Utah’s 13ers last summer, which was designed by nutritionist Roxanne Vogel.

“I was worried that I would either not feel full or crave more whole food, but I felt awesome,” says Nelson. “My pack was lighter [than carrying whole foods], the fuel was easy to consume and my energy levels were great.”

Multi-Day Sample Menu

Simple Carbohydrates with some Protein and Fat

This sample meal plan is designed for a 120-pound woman on a multi-day, self-supported run with access to additional whole foods (via a resupply or crew) for evening meals. It’s a far cry from the Pop Tarts and jellybeans I ate on my Sierra run, a lot more satisfying and ultimately will shift the memories made on the run from bonking to the amazing places two feet can take you.


  • Oatmeal mixed with peanut butter, banana, chia seeds, cinnamon, pumpkin seeds
  • Coffee if desired
  •  Sip on 10 to 20 ounces of sports drink until run start

Run Fuel

  •  45 to 60 grams of carbohydrates per hour, consisting of a mix of sports drink, gels, chews and real foods
  • 20 to 25 ounces fluids per hour including one serving sports drink plus additional water to thirst
  • ½ granola or energy bar
  • Two packages energy chews


  •  20 to 25 ounces fluids including one serving sports drink and additional water to thirst
  •  One PB&J sandwich
  •  ½ cup baked-potato pieces dipped in salt


  • Chocolate milk, if available, or whey protein recovery supplement mixed with water or 16 ounces tart cherry juice
  • One plain bagel


  • 1/4 plate white rice, 1/4 plate chicken, 1/4 plate steamed or sautéed veggies, topped with soy sauce to taste
  • Side of watermelon and additional sports drink or tart cherry juice

Timing Is Everything

To manage fuel consumption and keep energy levels steady, Kelly R. Jones MS, RD, CSSD, LDN, who works with endurance athletes, recommends scheduling your snacks.

“Prepare real-food mini meals, for example, to be eaten every three hours. PB&J sandwiches pack a lot of calories in small packages,” says Jones. “And then use sports-nutrition products such as gels and bars in between.”

Always test out your fueling strategy on training runs leading up to your multi-day adventure to dial in what sits well with your stomach and tastes good on the move.

Jones stresses that dehydration is the biggest issue runners face in these scenarios, which is where electrolyte drinks and salt loading come into play.

“I recommend using electrolyte formulas in most water bottles and then adding a bit of extra salt to foods ingested, including energy bars and bites, or mashed sweet potatoes,” says Jones. “Shoot for 300 to 500 milligrams per 24 ounces of water, considering all salt from food, gels and electrolyte packets.”

Ultimately most runners will need to utilize a combination of sports-nutrition products and real foods based on their event, digestion and taste preferences. Emphasize hydration, digestible carbohydrates, with touches of fat and protein for satiation.

Real-Food Fuel Bites

Nutritionist Kristen Chang created these Cashew Cookie Hemp Energy Bites as a simple portable recipe to fuel big-time adventure running with the right ratio of macronutrients.


  • 1 1/4 cups raw or roasted unsalted cashews
  • 1 cup raw pitted dates
  • 1/4 cup hemp-protein powder
  • 2 tablespoons maca-root powder
  • 1 1/2 tablespoons honey or pure maple
  • 1 tablespoon pure vanilla extract
  • 1/4 teaspoon sea salt
  • 1 tablespoon raw hemp hearts


  • Add all ingredients except hemp seeds to a food processor or high-quality blender
  • Pulse for 60 to 90 seconds, stopping every 20 or 30 seconds to scrape sides
  • Pour mixture onto a piece of parchment large enough to fold over top
  • Using a rolling pin and your hands, flatten the mixture to about 1/3– to 1/2-inch thick, and smooth the sides
  • Sprinkle hemp seeds over top and press lightly with hands so they stick
  • Cut into 10 rectangles or small squares

Follow Morgan Sjogren’s adventures on Instagram @running_bum_ and her blog, therunningbum.com.

This article originally appeared in the June 2018 issue of Trail Runner.

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