Rim to Rim to Rim: A Race and Fueling Guide

March 2024


“There are routes the boldness and logic of which are overwhelming.” - James Salter.

The Route

For me, the boldest route I could think of was running Rim to Rim to Rim in Grand Canyon National Park. Quite possibly one of the most difficult out-and-back routes I’ve ever done. Also, the most stunning route I’ve ever enjoyed running.

The Rim to Rim to Rim (R2R2R) is a 42-mile route not for the faint of heart. Though there are other options, runners usually complete on the South Kaibab and North Kaibab trails. Despite its apparent simplicity as an out-and-back journey, the intricacies of navigating the canyon contribute to the formidable challenge it presents. The standard route covers approximately 21.2. Upon reaching the North Rim, you turn around and retrace your steps to the starting point. Across the entire 42-mile span, you'll experience an elevation change of roughly 11,000 feet, both descending and ascending. The canyon's unique topography means embarking on a run that involves losing about 4,700 feet in the initial six and a half miles, only to regain that elevation in the final six and a half miles—a distinctive feature of this challenging course.

Additionally, the canyon is known for its harsh weather. It can be snowing on the North rim and balmy at Phantom Ranch (the very bottom). This makes fueling, hydration, and choosing gear particularly challenging. Typically, most runners attempt a double crossing in the late fall to ensure they don't encounter 90+ degree temps in the inner canyon, though it's not unheard of to have a hot day in November.

I must note that entering the inner gorge of the route exposes individuals to rocks dating back 1.8 billion years. Attempting to encapsulate both the route and the canyon in a few paragraphs doesn't fully convey their richness. The canyon unfolds a narrative woven with history, geology, and a touch of magic. Additionally, eleven tribes share connections with the Grand Canyon, adding diverse layers to its significance.

For those of you hoping to run this route, be it fast or otherwise, I wanted to share my strategy for fueling a decently quick trip across the canyon and back. My intention is that this guidance may assist others in navigating and savoring the beauty of this remarkable location.


The Logistics

Leading up to my R2R2R run, I was monomaniacal. I wanted to run the canyon quickly- I wasn’t aiming for an FKT, but I wanted to go fast, so planning, particularly my fueling strategy, would be key. Considering the limited water supply and fluctuating temperatures, I aimed to optimize my hydration strategy for the canyon adventure. Before the trip, I visited Skratch Labs HQ for a sweat test, revealing that I'm a salty sweater, losing about 1325mg of sodium per liter compared to the average of 800-1000mg. Armed with this knowledge, I tailored my hydration plan accordingly.

I wanted to limit the amount of stopping I did in the canyon, but obviously, I’d need to have enough water and food on me to make sure I felt good the whole day. Based on my drinking habits over the summer on long runs, I decided I’d need to have access to 4 liters of fluid- though most of that would need to be filled with Super High Carb mix and Sport Hydration.

Luckily, my partner George, and friend, Maddy, were up for a little adventure in the canyon and were both gracious enough to help me out with my run. Because of their generosity, I planned on using three different packs. George would carry an empty back to the bottom and fill it up for my return trip- from Phantom Ranch to the top of South Kaibab (6.5miles) and I mailed Maddy a pack will all the essentials to hand to me on the North Rim. I would start with a pack and drop it off with her. Each would be stocked with roughly the same things:

  • A liter bladder filled with two 200-calorie packs of Super High Carb mix (400 calories/400mg sodium)
  • Two packets of Sport Drink Mix (160 calories/760mg sodium) for a total of 560 cal/1160mg sodium
  • Two packets of Skratch Chews and a waffle for variety

Additionally, George would carry one 16oz flask that I would drink from whenever we were running together. On the way out it would have one packet of sports hydration and on the way back, it would be plain water. In total, I would have 1760 calories in my three packs and the additional outbound flask. I’d have 6 packs of chews (960 Calories) And 3 alt treats (420cal), totaling 3140 Calories.

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The Run

Before I get to the run, I’ll mention that I had some concerns about…err.. having a less-than-happy stomach in the canyon and wanted to be sure that I wouldnt find myself in need of a bathroom but unable to locate one. A day and a half before the run, I made sure I was on a low-residue diet- a whole lot of chicken and rice. While I don’t recommend this diet for long-term use, it is a tool to use to help reduce the amount of stuff in your digestive tract. The less stuff in there, the less stuff that needs to leave.

The morning of the run, I woke up early, 3:30am. I’ve found that eating a full meal about two hours before running seems to work the best for me. (read more about timing here!) I ate a decent portion of rice and chicken and drank black tea because I cannot function without tea. George set off 45 minutes ahead of me, walking and jogging to the bottom to conserve energy. And also not to totally annihilate his quads- the first downhill has a way of doing that.

Arriving at the South Kaibab trailhead by 5:25 am, I found myself beneath a clear, dark sky adorned with brilliant stars. The awareness of standing on the Grand Canyon's rim, about to descend nearly 5,000 feet, created an eerie yet captivating stillness and quietude around such a majestic spectacle.

Months of planning, training, and anxiety were about to come to life. At exactly 5:30am, I anticlimatically pressed start on my watch and dropped below the canyon rim. I felt like a diver headed into the depths of the ocean. I could only see where the light from my headlamp touched. It was 32 degrees F on the rim, but as I descended, the temperature began to climb and I soon found my gloves and arm sleeves to be unnecessary.

I didn’t consume much on the descent, as I was cold and focused on not tripping on anything, sending me soaring over a ledge. Just as I reached Tip Off, the first spot where the Colorado River is visible from South Kaibab Trail, the outlines of the canyon walls began to appear with a little more clarity. Down below, I saw a headlamp pointed my way. George had made it down safely.

George and I met up after I crossed over the bridge. For the next seven or so miles, we ran together. I drank mostly from the flask full of Skratch Sport Drink Mix that George carried, trying to conserve the liter bladder in my pack for when I would be alone. A little past Ribbon Falls, George turned back around. He planned to return to Phantom Ranch, wait for my arrival, provide a fresh pack, and then accompany me as we ran out of the canyon together.

For the next seven or so miles, I had the canyon mostly to myself. The temps were getting warmer, the people I saw were super friendly, and sunlight was slowly cascading down the looming canyon walls, hitting the bottom in some spots. I sipped on the Super High Carb mix and ate the gummies slowly, a little trepidacious about stomach issues. But, so far so good.

When I reached Manzanita Campground, I knew the grade was about to get exponentially steeper. It was now significantly hotter, especially with the heat reflecting off the canyon walls. And despite the higher altitude of the North Rim (over 8000ft) I was pretty toasty and was drinking from the pack more consistently. About a half mile from the rim, I ran out of water. Luckily, Maddy was waiting at the top with a fresh pack. I threw her my empty one (which also contained a postcard for her, talk about mail delivery service!) and put my phone (for photos!) and Garmin mini InReach into the new pack. And down we went.

At this point, my quads were trashed and I kept slamming my toes into rocks. While I didn’t completely fall, I knew I was likely going to lose more than one toenail after this (I lost three). Maddy stuck with me to Cottonwood Campground. A short way after that, she turned and headed back to her car on the North Rim and I continued.

Around mile 32, I was feeling good, but my quads were noticeably tired. My stomach felt great and I was in good spirits, but the pep in my step had faded. I was looking forward to going uphill. The heat of the day had settled into the canyon, hovering in the mid-70s. And I was drinking more than I thought. I ran out of water about two miles before Phantom Ranch.

When I saw George waiting by the river, I had been running for exactly six hours. He handed me my pack and the flask of plain water, which I held on to and emptied as we climbed out of the canyon. For the next six and a half miles, we hiked and trotted our way back to the rim. The conversation slowed, as did our pace. I was mostly dead focused on getting to the top. It’s amazing how much I wanted to be done considering I had been looking forward to this exact moment for the greater part of a year.

My excitement rose with each step closer to the end of the trail, closer to the point at which I could stop pushing my body, I tried to drink whenever I was thirsty and eat, but it was more of a struggle to remember to eat, more forceful and less natural, my mind, or maybe my body, was only focused on getting to the top. However, something peculiar occurred around half a mile from the top, right when you could see visitors peering down from above. Suddenly, the realization that it was all coming to an end truly struck me. While every fiber of my being yearned to cease movement, I wasn't ready for it to be over.

Typically, when fully engrossed in a significant endeavor, I try to maintain emotional composure to ensure a smooth journey and navigate any obstacles or setbacks with ease. It's essential to stay calm, cool, and collected, avoiding unnecessary stress. Yet, as I neared the conclusion, there was no need to "keep it together." Emotions welled up unexpectedly, leading to an incredibly unusual and poignant experience. George and I crested the rim. Just under 8 hours. I immediately sat down and tears welled in my eyes. I was exhausted, emotional, happy, sad, all the things all at once. The day had been absolutely perfect. Flawless. 

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The End

In the end, the obsessive planning, the logistics, the stewing over what to wear, and the months of training, it all culminated into one amazing experience.

To me, I love to plan. I find that executing something big like R2R2R well is so incredibly rewarding. All the planning and figuring out of things before I do the thing itself allows me to just be wherever I am, fully. I’m not worrying about if I’ll have enough water or food. If I’ve got what I need. It's already been thought of and planned for.

I’m incredibly thankful for George and Maddy- There is no way I could have had as good of a day if it weren’t for their willingness to be a part of this big scheme. My stomach never once felt bad during the run. Thanks to the Super High Carb mix, I never felt bonky. All in all, my moving time was 7:59, and I stopped for a total of four minutes on the run. I drank about three and a half liters of water, had five packs of chew, and one and a half waffles.

When we got back to the hotel, I slammed a protein smoothie and followed that up a few hours later with canned Rose, fries, and some ridiculous sandwich, which in retrospect did make my stomach not feel great. Can’t win ‘em all.

Click here for Strava Link


About Reese Ruland

Reese is an endurance runner and cyclist. She spends most of her free time riding, running, and eating poptarts in the mountains of Colorado. When she's not being active, she is normally drinking tea and taking videos of her French Bulldog, Loaf.

Follow Reese’s Adventures: @reeseruland

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