"What kind of 80-year-old do you want to be?” Kirkland Shave asked his 12 captives, posing a question that had hitherto permitted me just one answer: a living one.

“You have two choices. Do you want to be skiing at 80? Or do you want to be in diapers?”

Faced with such dilemmas in the past, I have usually opted for compromise—skiing in diapers, say—but Shave does not traffic in half-measures. Nor does Mountain Trek, the acclaimed fitness and hiking resort he has run for nearly 20 years from a remote, utterly idyllic spot in British Columbia, four hours north of Spokane, Washington.

The place is Ainsworth, a former mining town that possesses natural beauty of the type that palette knife painters on PBS have tried and failed to capture for years, or about as long, believe it or not, as Houstonians have been making pilgrimages to Mountain Trek. That’s no small thing, as said trek often requires two planes and a long bus ride, but we do it anyway, it seems, all in hopes of shedding excess poundage, crippling stress levels, smartphones, and just about everything else that defines Houston-ness in this new century. What does it take to slough off a Bayou City carapace, you ask? Just seven days at Mountain Trek, or so we’ve been told.

“Seventy percent are American, 20 percent Canadian,” Shave said of Mountain Trek’s demo, “and in the early years we got mostly Californians and New Yorkers.” Increasingly, though, he and his team are beset by Texans “looking to get reset and educated, and then they want to go back and figure out how they’re going to get the resources and infrastructure to support some life change.”

So it was that on a brisk afternoon last September, a dozen hopeful strangers from Dallas and Houston, but also DC, Boston, Seattle, Toronto, Chicago, and more, made their way to little Ainsworth and then up a steep hill, each eyeing the other with a wariness recalling the early rounds of Survivor. Whereas reality show contestants will do anything to avoid getting voted off the island, however, MT participants seem to crave nothing more, especially during the first dizzying days of detox. The program might seek only to reset, restart and, in the parlance of the accompanying handbook, “‘reboot’ an active, growth-centered, anabolic metabolism in five to seven days.” To the extent that such terminology suggests effortless change, however—pushing buttons, unplugging and then re-plugging oneself—it is woefully, almost criminally inaccurate.

No, Mountain Trek will not kill you. And yet there will be moments, moments when any reasonable person might question whether he will make it to the end of the week, much less the age of 80, and if so, what is so wrong with diapers?

The 12 trekkers tiptoed nervously into the lodge, whereupon they were immediately bum-rushed by a bevy of staffers eager to get the week’s guests settled into comfortable private rooms, some overlooking dense patches of pine through which the outlines of Kootenay Lake were intermittently visible. Next, all migrated to the lodge’s great room, where, to the tune of the fireplace’s crackle and pop, they awaited their fate.

“Some of you, especially those of you from cities, will have trouble getting used to how quiet it is here, how dark it is at night,” announced one of Shave’s many deputies, a winsome former journalist named Jaime. In short order, he explained that cellphones must be kept in airplane mode during the day and that Internet usage would be allowed only from 6 to 10 in the evenings, and only in one’s room. Yoga would commence promptly at 6:30 each morning, followed by hours-long hikes on mountain trails of varying degrees of difficulty, followed by lectures devoted to nutrition, sleep, stress management, and more, followed by further strenuous exercise in the evenings, this time of the kickboxing and CrossFit variety. Men and women would consume, respectively, 1,400 or 1,200 calories a day divided into six meals, none of which would include caffeine, sugar, alcohol, or anything else to which their livers might object. And lest anyone get the idea to, say, sneak down the hill to Ainsworth proper and order a pizza, there was this to consider: “Bear scat has been seen along the road, so I wouldn’t advise it.” 

As the litany of rules and warnings continued, several trekkers shot frightened glances at each other, the revelation dawning that Mountain Trek would be less weeklong-journey-of-discovery than a seven-day-ordeal. “This is not a vacation. It’s a bit of a suffer-fest,” as another staffer announced before bidding the 12 goodnight, reminding them to expect a knock on their doors promptly at six the next morning.

To the extent that such dramatic and expensive measures as Mountain Trek have become necessary ($5,000-plus per week), the human genome is to blame, it seems, or rather the stubborn constancy of that genome in the face of diets and habits that have deviated radically from those of our ancestors. “The DNA of homo sapiens has changed less than 1 percent since humans walked out of Africa 50,000 years ago,” as Shave put it during one afternoon lecture, “but we live nothing like the hunter-gatherers our genes prepared us for.”

Ancient Ainsworth types, for instance, “fished and harvested here, and then migrated to the Spokane area for the wintertime,” the implication being that their contemporaries in Chicago, Boston, and elsewhere eked out similar lives of nomadic desperation. For a moment I daydreamed about the lives of early Houstonians, imagining eons spent stomping through swamps, swatting mosquitos, and waiting for air-conditioning. Transported time-machine-style to the present day, it seemed unquestionable that our forebears would marvel at the Galleria’s temperate climate (Christmas excluded), our winning baseball team, and the year-round availability of Tex-Mex. But would they thrive? No, they would not. They would suffer from the same maladies that have induced their descendants to migrate annually to Mountain Trek.

The first morning’s weigh-in produced a blizzard of stats on BMI, fat percentage, water weight, and the like, all depressing numbers in need of vast improvement. Cue the daily routine: yoga, lung-burning hikes, lectures, exercise classes, and—finally!—evenings of restorative massages and trips to the MT hot tub and sauna. The gang of 12 seemed unfazed by their new normal, but only for the first day or so, after which the wheels began to come off. The ex-COO and the commercial pilot, the biotech executive and the real estate investor—movers and shakers all—swiftly realized the extent to which their high-power lives had been held together by bad habits, and reacted none too well to having those habits summarily stripped away. For a time cruelly decaffeinated humans wandered aimlessly about the lodge, stumbling in delirium, desperate for Epsom salts to soak their hike-compromised feet, capable of communicating only via phrases not sentences, grunting about quinoa and Ezekiel bread, crawling to and collapsing in their beds.

To be fair, Shave had warned the group this would happen, that they would “go through a little dip during the first couple of days—recalibrating, going through a bit of withdrawals, going through a bit of detoxification. And then, by Thursday and Friday it’s like five years or 10 years of your life have just slid off you.”

For a while it seemed like the group might not live to see another Thursday or Friday. Wild rumors began to circulate: that the woman from Seattle was hiding smuggled Lärabars in her hiking boots; that yoga was optional; that someone had located a daytime hot spot for wi-fi; that the bears would be too busy eating huckleberries to notice humans with pizza boxes.

But underneath this swirl of anger and doubt, transformations were indeed occurring. The personality of a hitherto taciturn Canadian bubbled to life, the face on a retired nurse began to glow, a formerly tetchy physician found his sense of humor. Meals once dismissed with a snort were finally appreciated for their deliciousness and ingenuity, flab was replaced by tautness, enduring friendships were forged, the verdant majesty of mountainous British Columbia was finally given its due. Most miraculously of all, these things happened to people whose days consisted of four times as much exercise and half as much food as the ones back home.

But such changes were accomplished by fervent appeals to mind as well as body, most notably during the daily lectures. Jen the nutritionist helped trekkers separate fact from fiction amid the “56 diets on the market today,” taught them about the “sour 8,” how to get probiotics from natural sources, and about the simple pleasures of Medjool dates stuffed with tahini. Simon’s sleep seminar counseled a bedroom temperature of 65 degrees and going screen-free 30 minutes before retiring, while from Sage they learned about exercise secrets of Olympic-level athletes, momentary muscular failure, and the evils of cortisol.

To a person, everyone looked back on the week not with anger but amazement. No one regretted the decision to come to BC for MT—the same decision that had led friends and families to shake their heads in disbelief—after witnessing startling improvements in BMIs, HGH, REMs, and the like. Indeed, for some it qualified as the vacation of their lives, if only because no other trip had ever led them to vacate their carapaces so completely. 

“I have the ultimate best job in the world,” said Shave during a reflective moment. “I’m helping people reclaim themselves, inspiring people to re-fall in love with their bodies and connect to nature. Every week I watch people come in with drawn faces, a bit slumped in the shoulders and wrinkled with stress lines—exhausted, basically.” And within days, “they’re walking with a lift in their step and their heads are up, they’re noticing things and smiling more, their skin is tighter and they’re radiating, not only physically but energetically.

“There’s nothing better than seeing that kind of transformation week after week.”

Weeklong stays at Mountain Trek’s British Columbia lodge run from Saturday to Saturday through October, and cost $5,400. A satellite version of the program, run by the same Mountain Trek team, is held during winter at the Hotel Domestique in South Carolina’s Blue Ridge Mountains. Visit mountaintrek.com for more information.