By Michael Lanza

“Umm, hey buddy, you okay?”

It’s 4:30 a.m., a time of day that puts us in the questionable company of cat burglars and alpinists. Our headlamp beams seem to bounce off the inky black of a moonless night in Yosemite Valley. Four of us are taking the first steps on the 221-mile John Muir Trail. And my friend Mark Fenton is staggering like a frat boy on a weekend bender.

“No problem, just a little vertigo I get hiking in the dark. I’ll be fine.” As if scripted for a sitcom, he then lurches too near the edge of the trail—which drops off into the dark roar of the Merced River far below.

From that moment on, he becomes known as Stumbles.

We laugh, because the nickname’s funny and appropriate, and because our packs weigh in at only six pounds, and because the four of us have trained and trained some more for the insane undertaking we’ve just begun—so we’re practically running uphill effortlessly, feeling as fit as racehorses. But mostly we laugh because we are only at the beginning of an odyssey that seemed impossible when we first contemplated the idea. We haven’t yet entered the zone of constant pain, so it’s easy to delude ourselves into believing that we aren’t pursuing an ambition of fools.

Besides, we’re in Yosemite, a place crazy with distractions. In the faint first light, 600-foot Nevada Falls looks like a wavering white apparition, and our inability to see it well seems to amplify the sound of the free-falling water sheering through air like a liquid guillotine. Deer bound away silently in the chilling dawn. At mid-morning, from ledges at 9,000 feet, we go slack-jawed at a shark’s grin of peaks: Tenaya, Tressider, Cathedral, Matthes Crest. We’re giddy as little girls, knowing this is just a scenic appetizer for the feast of alpine vistas awaiting us over the course of the week ahead on the JMT: snow-draped mountains and jagged granite spires, passes from 11,000 to over 13,000 feet, and a constellation of lakes reflecting it all upside down.

That’s right, I wrote “the week ahead.” We’re out here as guinea pigs testing a theory that, by arriving ultra-fit and going ultralight, we can collapse a hike normally stretched out over three weeks or more into seven days. We’re taking what Ray Jardine preached in The Pacific Crest Trail Hiker’s Handbook back in the 1990’s—a then-controversial gospel that called for drastically slashing pack weight and ramping up daily mileage—to a questionable extreme. The math sounds pretty simple: trim pack weight by two-thirds (or more), and hike three times as far. A lot of Ray’s disciples have since embraced the ultralight strategy with great satisfaction, including many Pacific Crest Trail thru-hikers, who would not complete that 2,600-mile thru-hike in one season without going light.

Hi, I’m Michael Lanza, creator of The Big Outside, which has made several top outdoors blog lists. Click here to sign up for my FREE email newsletter. Join The Big Outside to get full access to all of my blog’s stories. Click here to learn how I can help you plan your next trip. Please follow my adventures on Facebook, Twitter, Instagram, and Youtube.

I’ve made a steady evolution into that style of backpacking, going from regularly lugging 50-pound loads for eight or 10 arduous miles a day to carrying sub-30-pound packs on 15- or 20-mile days. Instead of suffering under an unwieldy load and taking five days to hike 40 miles, I’d walk more comfortably and finish in three days, or hike farther in the same five days, and feel less taxed physically. I’ve found it easier to train for walking farther with a moderate load than for walking less distance with a heavy one. And based on personal experience and what I’ve seen happen to other hikers, I’m convinced that backcountry injuries are more often attributable to excessive pack weight than to excessive miles.

To purist backpackers who object that I’m not stopping to smell the roses—or whatever it is one smells when bent double under a huge pack—I point out that I’ve simply gone from walking 2 mph to walking 3 mph. I’m not missing anything; in fact, I’m going farther and seeing more than I used to. But just finishing a day on the trail feeling great was evidence enough for me.

Get the right backpack for a hike like the JMT. See my picks for “The 10 Best Backpacking Packs”

and the best ultralight backpacks.

Mark Fenton on the JMT in Yosemite. On the JMT overlooking the Cathedral Range, Yosemite. Heather Dorn on the JMT below Cathedral Peak, Yosemite. JMT camp on a lake north of Donohue Pass, Yosemite. Todd Arndt reaching Donohue Pass in Yosemite. Banner Peak, Thousand Island Lake, John Muir Trail, Ansel Adams Wilderness. South of Donohue Pass, Ansel Adams Wilderness, High Sierra. Garnet Lake, Ansel Adams Wilderness. Above Cascade Valley on the JMT, John Muir Wilderness. Todd Arndt at Lake Virginia, John Muir Wilderness. Hiking to Silver Pass, John Muir Wilderness. Soaking feet, Silver Pass Creek, John Muir Wilderness. Heather Dorn’s feet at Silver Pass Creek, day four. Camp above Quail Meadows, John Muir Wilderness. Mark Fenton above Marie Lake, near Selden Pass. Todd Arndt above Marie Lake, near Selden Pass. Marie Lake, near Selden Pass. Todd in the South Fork San Joaquin River. Todd at Wanda Lake, John Muir Trail, Kings Canyon National Park. Helen Lake area, Kings Canyon N.P. View from JMT at Mather Pass, Kings Canyon N.P. Todd Arndt at dusk, Mather Pass, Kings Canyon N.P. Lake Marjorie, Kings Canyon N.P. Mark hiking to Pinchot Pass, Kings Canyon N.P. Hiking to Glen Pass, Kings Canyon N.P. Hiking to Forester Pass, Kings Canyon N.P. Descending south from Forester Pass, Sequoia N.P. Dollar Lake, Sixty Lakes Basin, Kings Canyon N.P. Mark Fenton at Trail Crest on Mt. Whitney.

Fastpacking the John Muir Trail

For a few years, the idea of speed-hiking the JMT had been stabbing the button of my obsessive-compulsive disorder, demanding my attention like a tiny thorn in my sock. I learned that fit hikers going überlight were sailing “America’s most beautiful trail,” as the JMT is often called, in just 10 days; it sounded reasonable, given the Sierra’s dry, mild summer weather and the trail’s moderate grades. Then I bumped into one ultralight guru who suggested cranking it in seven days. Another Muir Trail veteran told me that “30- to 40-mile days are totally doable.”

Unfortunately, where another hiker might think that pounding out 31 miles a day for a solid week sounds just slightly over the top, my admittedly altered brain chemistry rationalizes, “How hard could that be?” I also had the ulterior motive of simply wanting to hike the entire trail, but knowing I couldn’t possibly abandon my working wife and two young kids for three weeks. Before long, I’d convinced myself that a seven-day thru-hike of the JMT—221 miles including the 11-mile descent off Mt. Whitney (the 211-mile JMT terminates at its summit), with more than 40,000 feet of elevation gain—was not only feasible: It would even, quite possibly, be fun.

Right now, anyway, my prognostication is looking pretty good. At the risk of sounding cocky, we’re chewing up ground. We roll into Sunrise High Sierra Camp—nearly 13 miles out—by 10 a.m., as fresh as if we just did a 10-minute warm-up. The afternoon heat drains us, but we refuel on burgers, fries, and milkshakes at the Tuolumne Meadows café at around mile 22, and rendezvous with Mark’s wife and kids, who’ve driven there with our camping gear and a food resupply for the next two days. Then we set out again with 18-pound packs to hike into the evening.

Want to thru-hike the John Muir Trail? Click here for detailed, expert advice you won’t get elsewhere.

In the mountain dusk of 7 p.m., we pitch our tarps near a windswept, unnamed alpine tarn at 10,180 feet in Lyell Canyon. We pass the ibuprofen like we’re doing shots, rub tired-but-not-aching feet, and take stock. On our first day, we’ve walked 34 miles, with 7,000 feet of uphill. Mark’s pedometer reports the day’s mind-boggling tally: 72,376 steps. We should look like enemy combatants with open-ended leases at Guantanamo, but instead, we’re just tired.

As we take an icy dip in the lake, below a skyline of granite cliffs, Stumbles tells me with an ears-wide grin, “You know what? I can’t believe how good I feel.”

I smile, naively thinking: We’ve got this thing licked.

On the JMT overlooking the Cathedral Range, Yosemite.

Planning a John Muir Trail Thru-Hike

“Subject: Re: You’re going to do what in 7 days?!”

That was Mark’s response to my e-mail, months earlier, baiting him with a passing mention of my plan. Mark, who lives south of Boston, is an author of books on fitness walking and a former U.S. race-walking team member who’s now, like me, past 40 with a demanding career and a young family. I wanted him in, but knew I couldn’t just invite him outright. Mark’s a hyper-analytical MIT guy: He would react to this supremely irrational idea in a very rational way—dismissing it as a plan for masochists.

I knew that before agreeing to this level of insanity, he would have to go through something like the stages of grief: First there is denial (“No way I’m doing something that stupid”), then anger (“Why me?!”), followed by bargaining (“Okay, I’m tentatively in, but I reserve the right to back out at any time”), depression (“Oh, my God, we’re actually going to do this”), and finally, acceptance (“I’m an idiot”).

Honing my sales pitch as Fenton chewed on my proposal, I started recruiting a team of the blissfully ignorant.

My fellow-Idahoan friend Todd Arndt takes hours-long trail runs and still fondly recalls the time we hiked 8,000 feet up out of Hells Canyon—108° F., no shade. Todd’s a doctor, so if one of us perished—assuming it’s not him—at least we’d have someone who’s qualified to pronounce the time of death. When I called him and broached the idea, there followed a long pause, then he said slowly, as if he’d just bumped his head very hard: “That. Sounds. Great.”

Heather Dorn on the JMT below Cathedral Peak in Yosemite.

Heather Dorn, mother of two girls and living at the time in Pennsylvania, exhibited impeccable judgment—a valuable wilderness asset—by avoiding my calls and emails for weeks. But proving demonstrably that a Y chromosome is not a prerequisite for bad judgment, she ultimately gave in to the lure of the impossible disguised as plausible.

And Mark Godley, of the Bay Area, was tough enough for it: He had hiked with me through the rugged Bailey Range of the Olympics carrying a sleeping bag the size of a prize-winning pumpkin. In a two-career marriage with three preschool children, he couldn’t escape for a week, but would join us for our last two days.

And a month after that first e-mail to Fenton, he was in. Defying reason, I had a team.

We set out to get in the shape of our lives in four months—going out on 5 a.m. speed hikes, grinding out 25-mile dayhikes in blistering heat, doing ridiculous numbers of lunges. A few weeks prior to meeting up in Yosemite Valley, Fenton and I banged out a one-day, 32-mile hike of the Pemi Loop in New Hampshire’s White Mountains with 10,000 feet of ups and downs.

We were ready. Or so we thought.

Tell me what you think.

I spent a lot of time writing this story, so if you enjoyed it, please consider giving it a share using one of the buttons at right, and leave a comment or question at the bottom of this story. I’d really appreciate it.