Fueling at 19,000 Feet: What Worked (and What Didn’t) for the Kilimanjaro FKT

Fueling at high altitude is tough. Even with planning, training and every snack tested in advance, the mountain still had the final word. 

That’s the wild part of big efforts like this – they’re as much a science experiment as an endurance challenge. You line up your hypotheses, prep your data points (gels and chews) and then test everything against wind, elevation and sleep deprivation.

Spoiler alert: My partner, Brian Corgard, and I didn’t just complete the route. We established a new one and set the FKT (Fastest Known Time) on the Northern Route, also known as the Lemosho Lollipop, in 36:05.

This is what happened when the nutrition plan met 19,000+ feet on August 15th-16th, 2025.

Real-Time Pivot: School Hut Checkpoint

We had initially planned for two drop bags and checkpoints at Pofu and Barranco. During recon and after talking with our guides, we realized another stop would be necessary. 

So we added a checkpoint at School Hut (15K ft). We stashed warm gear, extra peelable layers, and yes, hot noodles. That added checkpoint saved us, and morale soared with that first sip of broth at 15K ft.

What Worked

Scheduled fueling: Alarms got calories in even when hunger checks were on mute.

Drop bag at School Hut: Worth it for the extra layers and that bonus serving of instant noodle soup.

SIS Beta Fuel: The only gels that consistently passed our stomach’s picky test in the final miles – lifesaver.

Hot soup at ~18K + ft: Our team coordinated with another crew so that when we rolled up to Stella Point, bowls of hot noodles were waiting. Best. Soup. Ever.

Recon fueling: We ate a lot during the recon, including warm soups, veggies, rice, desserts, snacks, second breakfast, sandwiches, pizza, Nutella and more. 

Turns out, this wasn’t just indulgence. Pre-event carbohydrate loading (especially with complete meals) is shown to improve glycogen storage and endurance performance at altitude¹.

What Didn’t

Appetite tanked quickly: We planned for ~300 calories per hour… reality was closer to 200. The higher and faster we climbed, the more our systems shut down. 

We expected it, just not so soon. Research confirms that hypoxia (low oxygen levels at high elevation) significantly alters appetite and energy balance via the hormones leptin and ghrelin².

One puke & descent magic: After descending to Barranco Camp (12K ft) and climbing up to Lava Tower at 15K ft, I got sick – classic altitude nausea. Luckily, we knew what to do and quickly descended. About 2,000 feet of downhill later, I was fine.

No noodles at Barranco: We’d planned to hit Barranco during daylight, not at night. Without warm food, morale dipped. Lesson learned: always prep for the unexpected, and bring the damn noodles.

Final note – some solid bars were excellent in training, but reviled during the FKT. Food fatigue is real.

Gut Training Pays Off (Until It Doesn’t)

We trained our guts like we trained our legs, with reps, intention and a healthy dose of discomfort. Every long run and climb in Colorado was another chance to test what our bodies could handle.

And for the most part, it worked. Gut training enabled us to absorb calories under stress. But even the best prep doesn’t erase the reality of 19K feet. Altitude still threw curveballs – there were moments when everything we packed looked disgusting.

So we fell back on the rule that carried us through:

Eat anyway.

Whether we liked it, wanted it, or dreaded it, we kept eating. A little here. A bite there. That’s what got us through.

Immediate Post- Kilimanjaro FKT Fueling

One thing that surprised us: just how wrecked our stomachs were right after the effort.

Especially me. For nearly two days, chewing food triggered nausea. Even looking at food caused me to feel queasy. 

I didn’t fully eat a meal until about 48 hours later, which meant I missed a critical recovery window. We knew it might be rough, but didn’t expect this level of post-effort gut shutdown.

What could we eat when we were at a lower elevation and a day after completing the FKT? Potato chips, plain rice, a bit of a bland mid-flight meal. No celebratory burger. No ice cream craving. Just basic carbs and salt.

Our authentic post-FKT meal didn’t happen until we got back to the States. The lesson? We should’ve prepped better for post-effort recovery in Tanzania. We ended at a remote trailhead with none of our tried-and-true post-effort foods to rely on.

There’s also science here: high-altitude exertion may increase gastrointestinal permeability and inflammation, which can contribute to nausea and reduced appetite post-exercise³⁴. Next time? We’re stashing post-epic-adventure comfort food at the end.

Recovery Fueling in the Weeks After

The Kilimanjaro FKT might’ve been done once we were back to the States, but the fueling wasn’t.

At first, we were confused. Why were we waking up at 5:00 AM with bottomless hunger? Why did it feel like we could eat everything and still be starving? 

Once we connected the dots, it all made sense: after high-altitude exertion, the recovery window can stretch well beyond the first few days – sometimes for up to a week or more, depending on altitude, nutrition and rest. For us? It felt like nearly two+ weeks of chasing fullness and strength.

In fact, studies recommend significantly increasing carbohydrate intake (up to 10–12 g/kg/day) in the days following ultra-endurance efforts, especially at elevation, to help with glycogen replenishment, inflammation and immune system support⁵.  

Given that my nausea and 24+ hours of travel set back our recovery window immediately post-effort, we were not even close to getting in enough carbs and other tasty foods!

Note for next time: recovery fueling starts at the finish line. Expect and embrace eating like a Hobbit for two weeks and beyond. And packing your go-to foods in advance is just as important as bringing extra socks.

Craving Burgers, Holding Memories

So, did we nail our Kilimanjaro fueling plan? Sort of. Did we eat enough? Almost. Did we puke? Yep. Did we finish? Hell yes.

Fueling at altitude is like speed dating with snacks; half the options make you nauseous, while the rest are absent when you need them most. But we kept eating (mostly), kept climbing (always), and somehow managed to laugh through the worst of it.

The real win? We set the route. We set the FKT. We raised nearly $3k for the Summit Scholarship Foundation. And we ate the damn food anyway.

Would we do it all again?

Ask us after we inhale a few more burgers.

References

¹ Burke, L. M., et al. (2001). Carbohydrate loading and exercise performance: A meta-analysis. International Journal of Sport Nutrition and Exercise Metabolism, 11(1), 28–54.

² Wasse, L. K., et al. (2012). Effect of acute exercise and hypoxia on appetite, energy intake and appetite-related hormones. Appetite, 58(2), 784–790. https://doi.org/10.1016/j.appet.2011.11.019

³ Pugh, L. G. C. E., et al. (1964). Muscle and liver glycogen in Man at high altitudes. Journal of Physiology, 175(1), 167–178. https://doi.org/10.1113/jphysiol.1964.sp007471

⁴ Costa, R. J. S., et al. (2017). Systematic review: exercise-induced gastrointestinal syndrome—implications for health and intestinal integrity in endurance athletes. Alimentary Pharmacology & Therapeutics, 46(3), 246–265. https://doi.org/10.1111/apt.14157

⁵ Impey, S. G., et al. (2020). Fueling strategies to optimize recovery after endurance exercise. International Journal of Environmental Research and Public Health, 17(11), 3980. https://doi.org/10.3390/ijerph17113980