R2R2R in One Day: Fueling Strategy, Heat Exhaustion, Public Tears

R2R2R in One Day: Fueling Strategy, Heat Exhaustion, Public Tears is a sponsored post brought to you by 4D.

What better way to spend your birthday than attempting a masochistic one-day run? On April 24th, I ran the Grand Canyon’s Rim to Rim to Rim (R2R2R) in one day from the Bright Angel Trailhead: 48.5 miles and 11,000 feet of elevation gain. Training-wise, I was fairly underprepared but mentally ready for the pain. Otherwise, I attribute my success in fighting 90-degree temperatures to a few key fueling strategies I made.

The last climb out of the canyon in the heat of the day was undoubtedly the toughest physical challenge I have ever faced. My body had already been moving for 12 hours, with an hour of sleep the night before. To top it off, I hadn’t experienced 90-degree heat since last September and have been training in comfortable winter temperatures the last six months. However, if I had to prepare again, I wouldn’t have changed much more than my clothing strategy. My food and water intake were solid, and I used 4D, a clean energy fuel, as my secret weapon.

R2R2R at the Grand Canyon in One Day

What I Ate

I took my second 4D of the day around mile 30. Subsequently, miles 30-38 were my favorite of the day.

Unfortunately, I battled nausea all day. My strategy of eating six slices of pizza the night before most definitely backfired, and I struggled to get down any real food. Because of this, I’m extremely grateful I had solid options for energy that didn’t involve choking down leftover pizza.

I’ve been using 4D for the past couple of months before my long training runs, and have really pleased with how well I feel. Though there are numerous benefits to their clean energy blends, I’ve used them solely to improve athletic performance. The biggest difference I’ve noticed is decreased muscle fatigue on long runs and a quicker recovery. Because they worked so well on my long training runs (which I didn’t do nearly enough of), I was really excited to take these to the Grand Canyon with me.

I couldn’t stomach any of the “real” food I had brought with me, so I just snacked all day. This wasn’t what I was hoping for, but I guess I can rely on 90% carbs and sugar for 17 hours.

Around hour 10 I had finished my descent of the North Rim and had about 18 miles to go. The sun was rising, and my calves were already on fire. I stopped for a long water refill and took the time to drink another 4D blend. When I started to run again my legs felt decent, and I powered past the 50k mark at a steady pace. Though the last 8 miles were a hellish death march, I definitely attribute my relatively comfy miles 30-38 to the boost in energy and focus I get from 4D.

What I Wore

r2r2r in one day

At the North Rim. Only halfway done and already looking pretty haggard. My Houdini has clearly been shoved into a vest or two.

When I started around midnight, it was 35 degrees and windy on the South Rim. So like a dummy, I wore a long sleeve shirt instead of the lightweight merino short sleeve I had planned. This was my biggest clothing mistake, and other than that I was pretty happy with my strategy.

Very unhappy with that decision. As soon as I began my descent I knew I would not need a long sleeve at the bottom. It’s also not a sun shirt designed for breathability or UPF, so this was a bad call all-around.

My trail running go-to. It’s the perfect extra layer for wind or stopping a chill from setting in while stopping for water. Furthermore, it’s only 3.4 ounces and fits in pretty much any pack or pocket.

These have a built-in liner and adjustable drawstring, and so far have been long enough to fend off the deadly inner-thigh chafe.

I spent most of the day running in shorts, but I started out in these and packed them in the case of extreme chafing (par for the course for me). They’re extremely lightweight and 1000% more comfortable to run in than leggings.

I’m sooooooo obsessed with Altra’s latest version of their Lone Peaks. My feet were the least of my worries, and I finished without any blisters or foot fatigue. 12/10.

It might have been a little warm for these, but overall my feet were happy.

  • Running vest: Borrowed from a friend

I used a 10-liter hydration pack borrowed from an angel of a friend, and it was absolutely amazing. It’s a European brand that I can’t find anywhere, but this Salomon one is fairly comparable.

This was my first time running with poles, and I absolutely will bring them for more long days like this. My pack had a place to strap them when I didn’t use them for the flats, but they were a leg saver on the climbs.

R2R2R in One Day: Running for 17 Hours Straight

r2r2r in one day

Views like this take the edge off the heat.

Long-distance trail running and ultralight backpacking share a lot in common. I move more or less at the same pace on the uphills and run/jog the downhills and flats. However, for something like Rim to Rim to Rim, I was extra conscious to take it easy on the downhills and save my quads. So, for most of the day, I was moving between 4 and 5 mph.

My two biggest hurdles were the heat and total body exhaustion at the end. Because I took it slowly and fueled well, my legs and lungs were holding up just fine. However, I had to stop for a one-minute rest roughly every half-mile for the last couple of hours. I kept myself mentally engaged by counting my steps and repeating “strong mind, strong legs.”

Why Do I Already Want to Do It Again?

R2R2R in one day: look at all those runners putting themselves through agony alongside me.

Though I ran by myself, I was not at all alone in my endeavor. There were roughly 30 other runners doing a one-day trip of Rim to Rim to Rim. Also, the nature of the trail means we crossed paths at least once. After a year of canceled races and events, connecting with the ultrarunning community in such an organic setting was amazing. Also, though the trail itself is hard as hell and requires serious mental and physical strength, it’s relatively accessible and safe (if you’re prepared). There are water taps along the way, and the number of people around makes a solo trip less daunting.

In the last eight miles, I struggled more than I ever have physically. The heat was killing me, and at that point, I had been awake for over 30 hours and moving for 14. I trudged up the climb under the sun, and the pain was clearly noticeable because multiple people asked if they could offer snacks, water, anything. I was completely capable of getting myself back to the top, but the feeling of community that comes from a solo endeavor is what makes me want to plan another trip.

The last few miles were so profoundly painful that I thought I would be too drained to feel anything emotionally at the top. However, as soon as I saw the Bright Angel Trailhead, I had a full public meltdown. I ran nearly 50 miles with 11k of vert in roughly 17 hours, by myself on my birthday. The amount of self-confidence and love that came with the South Rim summit is inexplicable, and I’m already ready to chase down that feeling again.

Featured image via.

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Comments 7

  • Steve : May 15th

    Katie, I did something similar to your Grand Canyon run and cannot understand how you ran in the dark. Was it full moon? Flashlight or headlamp? Even so, the descent and climb were danger in the dark forcing a slow pace. What am I missing?

    • B : May 15th

      Great achievement. Once I started reading though it just felt like an ad. Didn’t finish. Authors need to be more upfront about their sponsors, or if they’re not. Pitching products should be upfront.

      • Katie Kommer : May 17th

        Hey there! Thanks for taking the time to give your feedback. That’s exactly why we write who is sponsoring the post (if it’s sponsored) right after the title. Sponsored posts are great because they allow us all to take the time to write about our adventures and make a living 🙂

    • Katie Kommer : May 17th

      Hi Steve! I used a headlamp and felt totally safe. There were a handful of other runners / hikers around me, so I never felt alone out there! I have also done the trail a couple of times before, so I knew what was ahead of me the entire time. I hope this is helpful!


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