There are many ways to fail at the MR340. Each year, hundreds of boats launch into this competition along the Missouri River between Kansas City and St. Charles—the world’s longest nonstop paddling race, at 340 miles—and scores of them end up with the status “DNF,” or did not finish. The event’s organizers commonly diagnose that fate as “death by a thousand cuts.” It’s not merely that the paddlers were sunburned, parched, hallucinating, and aching feverishly after several days on the river. Those miseries befall almost everyone out there, to a degree. It’s that, in addition to all those things, they got nasty blisters or maybe puked on their smartphone. Something minor pushed them over the edge. It happens. All of which invites one to wonder why folks endure any of this in the first place.
In the 2021 book The Sweet Spot: The Pleasures of Suffering and the Search for Meaning, the University of Toronto psychologist Paul Bloom wrote that there are all kinds of reasons people choose to do fiendishly hard things. Some chase “flow,” or intense absorption in a task. Some seek to prove their toughness to themselves or others. Some crave the communal bonds of shared (albeit elective) suffering. In these senses, the MR340 resembles a marathon.
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Yet it’s unique in this respect: You’re by turns fighting, allying with, and surrendering to a watery force that’s more ancient and muscular than any one human striver—a force that drew our forebears to this fold of the continent, a force that right now blubs inside most of our bodies. (About 80 percent of St. Louis’ drinking water comes from the Missouri.) That’s not to suggest the race reconnects you to some kind of pristine natural feature. Americans have labored for generations to tame, straighten, deepen, and speed up the Missouri for commercial shipping. But the river isn’t really there for those purposes, or any of our purposes. It’s just there—both fact and mystery, fixed and in motion. You cannot step into the same river twice, aphorized the philosopher Heraclitus. Perhaps equally true is that the river can’t be raced on for 340 miles by the same you twice, because the you who tries it becomes distinct from the you who hasn’t. Most racers seem to prefer the versions of themselves who try it.
Clearly, the race does something to people. I saw this firsthand, in 2024, at the finish line party, which is always held at Lewis & Clark Boat House and Museum, in St. Charles’ historic district. The tradition is that the heavy-lidded racers and their entourages all migrate with their beers down to the landing and welcome in the final boat with whoops, claps, and cowbell clangs. On that sweltering evening, I watched as a 68-year-old solo racer floated in. She looked both confused and tickled by all the attention. A friend helped her stand up. The cheers swelled. Glancing around, I noticed quite a few racers (and race organizers) wiping away tears.
I would later learn a compelling statistic: About half the field in a given year is composed of repeat participants. They know about the suffering, and yet they come back. I concluded that the only way to truly grasp the MR340 was to finish it. So, in its 20th year, I decided to try.
The MR340 is often referred to as a race, but it’s really a clutch of sub-races. While elite competitors strive to place overall, much of the field cares more about their particular division because that’s the apples-to-apples comparison. Divisions vary by vessel (canoe, kayak, stand-up paddleboard, pedal drive, rowboat), by the sex of the paddlers (men’s, women’s, and mixed), and by the number of paddlers (ranging from solos to crews of 10 plus). Then, even within a division, some folks aspire only to finish, yet they too are racing—against the clock. At the back of the race crawls a safety boat called the Reaper. Its windshield is painted with glowering-beast eyes. It arrives at each of a half-dozen checkpoints at precise, publicized hours. If the Reaper beats you to any checkpoint, you’re knocked out of the race. So, given the ever-present risk of surprise snafus that can take hours to resolve (e.g., fog, heat exhaustion), you can’t lollygag. Yes, you can sleep a bit here and there, but you do, in fact, fear the Reaper.
I recently asked the race’s co-founder, Scott Mansker, whether such a frenetic contest is what he’d originally intended. It contrasts with how he himself got bit by the riparian bug, which was this: In 1989, he and his high-school pals in the Kansas City area built a raft and pushed it out onto the river. They had no idea what they were doing. But they floated from sandbar to sandbar, well into the night. “I was absolutely hooked to be on this raft, under the stars, under the moon,” he recalled. “We just couldn’t believe this was in our backyard.” For years afterward, Mansker would invite others out onto the river and watch, over and over, as they awoke to the glories of that aquatic playground. He concluded, however, that the best way to coax people out there was not open-ended exploration, but rather, something with a clear structure and timeframe. Thus he applied for permits and put together the first MR340, in 2006. Twenty people showed up with 15 boats. His goal was for at least one boat to finish and nobody to die. He succeeded, and the local news media ate it up. Cut to 2025, when the race—now run by the nonprofit Missouri River Relief and sponsored by Missouri American Water—would attract 353 boats with 542 paddlers from 36 states to the start. One of those paddlers was me.
I’d heard from river-rat sources that having a teammate increases the likelihood of finishing the MR340, so I approached Jason Deem, my onetime college roommate. A 6-foot-2 redeveloper of old buildings, he has an engineer’s brain, prefers to eat once daily (because it’s efficient), automates most life tasks, resents authority, and occasionally tolerates my presence. He agreed to do it. He even searched online and bought, from an MR340 veteran, a used tandem kayak. When you register for the race, you’re encouraged to enter a creative boat name. Some examples from 2025: Nauti Buoyz, Les Missouribles, Fighting Uruk Hai, Order of the Moon & Fog, Oar Force One. We named our boat the Green Machine. Because it was green.
We practiced on the river itself. We practiced capsizing and self-rescue. We practiced using RaceOwl, the smartphone app that tells you, on a map and via audio feedback, where your boat is in relation to the Missouri’s navigation channel. That’s crucial intel: You avoid the channel if any barges approach, because they’re obliged to stay within it, but otherwise, you cling to the channel. Suppose that the water there, on a regular day, is flowing 0.5 mph faster than the water on the edges. Even that small difference, multiplied over days, can spare you hours of toil and keep the Reaper aft. Yet it’s possible to stay in the channel without using RaceOwl, at least in the daytime. Markers on the banks tell you roughly where the channel is headed, and certain paddlers prefer to read the river’s surface: They aim for the boils, because those indicate where the biggest submerged sand dunes are, which indicate where the fastest water is.
Some of our prep was individual. My left shoulder has a tiny labral tear, so in the run-up to July, I drove out to Creve Coeur Lake alone several times and paddled out on rental kayaks to see how that felt. The first time I did this, an Asian carp leapt from the water and hit me in the face. (They prefer slack water, so they’re only a minor hazard on the Missouri’s channel, but one year, race organizers say, a racer who got nailed by a carp at a vulnerable moment in his paddlestroke had to exit the race and later get surgery.)
Another goal of mine at Creve Coeur Lake was to acclimatize. Heat stress is the most common medical emergency in the MR340, and I’m an office dweller used to A.C. Reportedly, though, doing physical activity in the heat for 60 to 90 minutes a day for a couple of weeks before the race is all your body needs to adapt: Your heart rate lowers, you produce more sweat and heat-shock proteins, and you retain more salts. So I dutifully did this for a fortnight—the same amount of time it took, incidentally, to get the fish’s stink out of my 50+ UPF sun shirt (true story).
We also recruited our old buddy Andy to help us. While some racers go “unsupported,” the vast majority have “ground crews”—friends or family who follow your progress on RaceOwl and meet you on boat ramps to resupply you with essentials and make sure that your fatigue-addled mind is making wise choices. Andy agreed to be our ground crew, so with the Green Machine bungeed to a trailer, we climbed into his Suburban on July 7, rolled out to Kansas City, and slept at a hotel.
Early the next morning, during a quick shower, I lost my balance and tumbled through the shower curtain and onto the bathroom floor, for no reason. (Jason assumed from the thud that I’d dropped a heavy box.) It hurt but whatever. Then we drove to the parking lot near Kaw Point, where the race kicks off, and when we lifted open the Suburban’s back hatch, my meticulously organized tub of food spilled onto the pavement. This was at 6:37 a.m. Things were going great.
But even the parking lot had an irresistible tailgate vibe. One ground crew was grilling. Cars had their windows painted. (One declared its team was powered by, inter alia, Red Bull, Advil, and R.E.M.) Racers in PFDs (personal flotation devices) and wide-brimmed hats bustled like rodents, moving objects in and out of vehicles. We joined the long stream of racers and crews pulling wagons of gear under elevated highways to reach Kaw Point, where a DJ was pounding out dance anthems and hundreds of solo racers, already arrayed across the water, waited until the 7 a.m. airhorn—then splashed away. We retrieved our boat, which we’d dropped off the day before, and lugged it toward the ramp for the 8 a.m. team start.
In previous years, this single boat ramp at Kaw had been a tangle: long lines and the silent panic of Midwesterners who fear being late yet are powerless to speed things up. This year was calmer. The main reason was that Big Muddy Adventures, the St. Louis–headquartered big-river outfitter, had come early and thrown down some wood pallets onto the muddy riverbank about 100 yards from the ramp, thus creating a second access point. This relieved congestion. The outfitter’s shaggy-haired founder, “Big Muddy” Mike Clark, assumed his customary role at the main ramp’s bottom, ankle-deep in the water, directing traffic. He helped Jason and me drop into the Green Machine. “You’re gonna love the hallucinations,” he said. “They’re the best.”
We sized up the other boats. Most were tandem canoes and kayaks like ours, but we did see a freakish-looking pedal drive and a dragon boat with more than a dozen paddlers. (I heard tell of, but didn’t see, a racer wearing only a Speedo and bandana.) The DJ counted down, the airhorn blasted, paddles flitted and sparkled, and we all merged into the Missouri’s channel—and directly into a fetid cloud of stink from some wastewater treatment ponds nearby. Thanks, Kansas City.
Minute 1 of 4,432.
By noon, my legs were twitching so hard, I knew we had to stop: The agony of major-league cramps would’ve launched me out of the boat. So we texted Andy our plans, veered off the channel, and came to the first paddlestop at Lexington, at race mile 51. As soon as I pushed up from the cockpit, my abs and thighs seized. I pitched sideways into the water and lost my shoe. Andy retrieved it and helped me up the ramp to stretch and drink water. Jason went off to pee somewhere. Our goal was to stop for 10 minutes. When we shoved off again, we’d spent 25 minutes going nowhere. This is why we’d been told by so many veterans: Stay in the boat and stay on the water. Even if you’re resting, you’re still getting free miles from the current. Lessons learned—about that, about hydrating, and about the MR340 time warp.
We glided into the first checkpoint at Waverly at 7 p.m., just an hour in front of the Reaper—a worrisome signal. I knew from following the race in 2024 that Waverly would be bonkers. It was. At that early stage, the field hasn’t fully spread out along the river, so everyone’s jockeying for space, at the same time, on the same two ramps, both of which sit alongside open railroad tracks (and freight trains do rip through there). But Waverly is a good place to take stock. It’s where seats are adjusted and fingers re-taped; bow and stern lights are affixed for the night ahead; porta-potties are visited briskly while mouth-breathing. I saw ground crews ply sun-dazed racers with iced tea and tupperware containers of sliced melon. Some racers scarfed down cheeseburgers at Boy Scout Troop 243’s tent or even gulped a quick beer. We heard two safety boats near the ramp bang into each other. Ramp volunteers in neon-yellow vests sweated in the late sun, shouting and hauling boats up and down. It was a zoo.
Once we pushed back onto the water, though, the sun sank. The chitchat among boats hushed. Everyone hunkered down in the dark. We drifted past Hill’s Island, where someone stoked a bonfire on the beach. A full moon rose and pursued us from behind the tree line. Over the years, several racers have described what it’s like to squint into the night and discern, in front of you, a long string of lights from MR340 boats arcing along a river bend. They were right: It makes you feel like you’re in a sacred navy of weirdos.
Over the years, several racers have described what it’s like to squint into the night and discern, in front of you, a long string of lights from MR340 boats arcing along a river bend. They were right: It makes you feel like you’re in a sacred navy of weirdos.
We’d also been told that, once night fell, we’d get a second wind. This, too, proved true. The air cooled our faces; at midnight, we treated ourselves to king-size Snickers bars provided by Andy. We caught whiffs of animal manure and stored grain. Jason turned on his speaker and jammed out an Americana playlist, but in the wee hours, we had to lower the volume. We nearly smacked into a buoy because we hadn’t heard the riffles in the water. That easily could’ve capsized us.
Then we ran into fog. Fog is very bad news in the MR340. To brave it is to court a serious crash or a level of disorientation so total it can lead to your paddling upstream. (Race organizers insist that this does, in fact, occur.) But, on the other hand, to wait out the fog on the riverside is to languish on rocks or mud, swatting mosquitoes, with nowhere pleasant enough to snooze—a waste of a break. In this case, the fog seemed patchy enough to plow onward. So we did.
The hallucinations came at around 3 a.m. I’d heard of folks seeing gorillas, giant anime dogs, ghost trains—and sometimes, a team will share the same hallucination. As for me, I knew things were awry when I tried to focus on stars and they squirmed. The trees on the bank started spelling huge gobbledygook words, then they shape-shifted into monsters who wanted to eat us. A safety boat far ahead was sweeping the bank with a flashlight’s beam, causing Jason to steer hard to the right to avoid an oncoming barge that didn’t exist.
Sometime after 4 a.m., our muscles and minds failing, we landed at the Dalton Bottoms paddlestop. Up the ramp and on the grass, other racers had already pitched tents, so we uncurled our sleeping pads onto the gravel parking lot and tried to sleep. But within 15 minutes, I was cold. We were still wet. (This is why officially required gear includes dry, warm clothes.) I rose to fetch my rain jacket, glanced toward the river, and said aloud, “Whoa”: Thick fog had blanketed the water. Good thing we’d stopped.
To say we “slept” for the next 90 minutes, though, would be generous. I took naproxen and that numbed some pains, but more were coming. Jason walked over with a wide-eyed look that meant, This is insane. “I guess we have to do this,” he said. So we got back on the river.
That was the first 24 hours. Full disclosure: The next 50 were a blurry, broiling triage that I didn’t document closely. I’d stashed inside the pocket of my PFD a digital voice recorder, expecting to dictate thoughts and observations, but here’s a truth of the MR340: To guarantee a finish, you can’t allow yourself much downtime. There’s always something urgent to do. Paddling is urgent. Even falling asleep is urgent. And even when we both felt the febrile weight of heat exhaustion (four times in three days) and pulled over to take dips into the river, we were hyper-focused on small changes in our body temperatures, because that would enable us to re-start paddling. The task at hand was all-consuming, for three straight days and nights. This is roughly what Bloom meant by “flow.” It’s intoxicating—and draining.
Another truth is that, for many racers, the finish is anticlimactic. Some of that is just psychological: You’ve steeled yourself for the long haul, so your brain refuses to accept it’s over. Some of it is just logistics: Jason and I finished at the ho-hum hour of 9:52 a.m. on a Friday—a moment when friends and family were busy with normal life. (Even though, ironically, their following us on RaceOwl had been a motivator; without an audience back home, we might’ve surrendered.) Our finish time was just under 74 hours. That was about seven hours slower than the median, but about 11 hours ahead of the Reaper. So could we have slept more? Yes. But we didn’t know that until late in the game. Boats and bodies break down easily out there.
We returned that evening for the finish party, where a bit of history was celebrated: Salli O’Donnell had beat everyone to St. Charles with a time of 39:42, thus becoming the first female top solo finisher. (Because solos start an hour earlier than teams do, the second boat to arrive, a men’s tandem pedal drive, had the overall fastest time of 39:25.)
During the awards ceremony, the race director, Steve Schnarr, addressed the crowd. He praised not only his team at Missouri River Relief but also the army of volunteers who, in their generosity of spirit and willingness to suffer for strangers, somehow brought order to the MR340’s chaos. “Nothing is certain; we all have to think on our feet,” said Schnarr, wearing only one sock to protect a toenail injury. Then Mansker took the mic. He reflected on this race he’d founded 20 years earlier. “It takes a leap of faith to do something that people think is a dumb idea, a dangerous idea, an impossible idea,” he said. “But it’s so cool to spend this week with you guys where I watch you take multiple leaps of faith… Watching people leave a perfectly good boat ramp and paddle off in the dark, swirling, muddy water in the middle of the night—I mean, that is impressive bravery.”
“ It takes a leap of faith to do something that people think is a dumb idea, a dangerous idea, an impossible idea.”
And indeed, a lot of MR340 lore is about calamity and courage. Jason and I ourselves heard and then watched, for instance, a rower slam into a buoy and get knocked into the water. (He ended up being fine.) Last year, I was tagging along on a safety boat, and at one point, it took a bad angle into a monstrous barge wake, and everyone on board got tossed around like rag dolls. Perhaps the all-time craziest MR340 story ever, though, was told to Jason and me by the man who’d lived it: Barry McCullough, a soloist who sidled up next to us at Weldon Spring on our fourth and final morning. We chatted and, slowly, out came his story from 2024: He and a few other paddlers had misread some lights and came too close to a stationary barge and sand dredge. Trying to get around them, McCullough hit the guyline for the anchor and tipped out of his kayak. With one arm holding onto his boat, he tried to kick to shore, but the current was pulling him toward the barge. He took a deep breath and got sucked under. Barges are typically about 200 feet long. He recalls his life jacket pinging him up along the barge’s bottom for about one minute. His thoughts raced to his wife, to his family, and to the realization that this was a stupid way to die. Then, finally, he popped out the back, gasping for air. He then resolved to return to the MR340. And there he was, in 2025, paddling next to Jason and me, racing again, finishing the thing on his own terms.
But I would argue that such wild stories obscure what the MR340 is really like. Finishing is not one grand gesture—not the jump shot at the buzzer, nor the goal scored in overtime—but rather, a series of countless small, unsexy decisions. Decisions to sip water. To remember to paddle with your core and not your shoulders. To stuff a handful of almonds into your face. To accept, viscerally accept, that you have 4.25 hours before the next paddlestop, as the sun roasts your back. To breathe and sip more water. To look upward such that your hat’s brim barely blocks the sun and to notice that the sky overhead is a limitless scroll of white sycamore fuzzies. To see, at twilight, amid the aching bluffs between Hermann and New Haven, a full moon rearing up, a scoop of electric orange sherbet. Noticing that stuff helps you through. Overall, the MR340 is an encyclopedic sampling of discomforts and then tiny moments of relief in which you appreciate mundane things—the fat in a stick of string cheese, the cloud that makes shade.
Asked why racers return again and again, Mansker offered a couple of reasons. One was that, given enough distance from your previous race, you start to look at your finish time as flabby and wrong. You wonder: What if I’d used a better boat? What if I’d slept less or skipped certain ramps? What if I’d eaten better? It becomes a puzzle to be solved, a machine to be tinkered with. But Mansker also offers another reason. “The lack of sleep and absolute exhaustion does something,” he says. “It brings your emotions closer to the surface. And so paddlers have said, ‘Well, I cried at every sunrise, and I cried at every sunset’—just touched by things that we ignore or filter, usually. Or you’re thinking about loved ones that are no longer around, tapping into those loved ones for strength. It just gives you access to emotions that you kind of suppress or don’t pay attention to.”
To finish the MR340, then, as far as I can see, is to be persuaded that attending to the present, however messy, has its rewards. That having a lethal force below you for 340 miles can clarify what’s right in front of you. That while you may never venture out on that big river, you’re already out on another, whether you choose to paddle through its shadows toward full moons or you don’t.
Editor’s Note: This is an updated version of the feature “Paddle-tested,” which was published in the October 2025 issue of St. Louis Magazine. For more stories about the Outdoors, subscribe to our Outdoors newsletter here.
