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Hike it off: Jeff Belanger Leads the Pack in Big Bend.
Silberberg (left) promotes healthy eating, not deprivation.
“Does this pack make me look fat?”
Sarah Sexton is playing it for laughs as she tightens the hipbelt on her backpack. Now that she mentions it, the cinched nylon webbing does create a visible belly roll. I keep that observation to myself.
“Yeah, and how about my thighs?” chuckles Dan Shattuck as he hikes the hem of his shorts to expose a generous—though muscled—quad and hamstring. He does an abbreviated runway strut for emphasis. “Are they flabby?”
Modesty is an early victim on most backpacking trips, but the group I’m hiking with in Texas’s Big Bend National Park has taken over-sharing to the extreme. We’re way beyond hat hair and funky feet and off into discussing taboos like thigh rub, secret food binges, and body image. If it’s connected to being, ahem, weight-challenged, it’s fair game. What else should one expect from an outfitted adventure billed as “Fatpacking”?
Five of us have trudged to pine-shaded Boot Canyon, in the lee of 7,825-foot Emory Peak, in the care of Fatpacking owner and head guide Steve Silberberg and his assistant Joan Hennes. We’re on a weeklong November backpack tour of the national park and neighboring Big Bend Ranch State Natural Area. And like most of America, we’re on a mission to lose weight.
Not that Dan and Sarah look, well, really fat. Neither do the other paying clients: Jeff, a military contractor from Washington, D.C., or Susan, a financial analyst from New York City. They look husky maybe, or full-figured, but on the whole kind of average. The numbers tell a different story. At 5’4” and 167 pounds, Sarah, a surgical nurse from Des Moines, Iowa, meets the medical definition of “overweight.” With a body mass index of nearly 29, she’s a short step away from obesity. (BMI calculates healthy body weight based on height and weight. A BMI of 25 to 29 is defined as overweight; 30 or greater is obese. Check yours on page 77.) Dan is already there. At 5’8” and 206, he has a BMI of 31. He runs, hikes, and lifts weights, yet this Bradenton, Florida, property manager is clinically obese. They may look “average,” but Sarah, Dan, Jeff, and Susan have gone flabby. An astounding 68 percent of adults in the United States are now either overweight or obese—which explains why none of us should be satisfied with looking average.
Exasperated, each of my tripmates had decided it was time to change. Instead of resorting to Jenny Craig or South Beach, though, they’d sought out Silberberg’s six-year-old Fatpacking program. The Massachusetts-based outfitter runs treks in national parks and wilderness areas coast to coast, and he claims results that Canyon Ranch, Camp La Jolla, and other weight-loss centers would gladly promote. (And at a fraction of the cost: the tab for Big Bend: $1,050. A week at Canyon Ranch: $6,920.)
On average, a man my age, height, and weight (48, 5’11”, 186 pounds) sheds about three pounds of fat during a week of Fatpacking. That might seem modest, but a heavier, more out of shape version of me—let’s say I tipped the scales at 225 pounds, with a BMI of 31—might drop twice that amount of body fat, the equivalent of a standard two-person tent. But Silberberg does not make specific weight-loss predictions, and opposes the fixation on numbers. More valuable, he says, is what I’d gain: added muscle, a healthier body composition, an improved metabolism, and an easy, inexpensive weight-control routine that I can enjoy for the rest of my life—no gyms, barbells, or high-colonic cleanses required.
It’s a tantalizing promise: fun, adventure, chiseled legs, and a permanently lean midsection. But will it work for out-of-shape wilderness newbies? That’s what I’d come to find out. That, and whether it could shrink the new spare tire around my own baby boomer belly.
As a fitness guru, Silberberg plays against type. There’s not a hint of Richard Simmons in his permanently tousled brown hair, crooked grin, and laid-back style. And his soft sell, online and in person, provides a relief from the infomercial diet du jour. Silberberg doesn’t regale with tales of personal redemption. He’s never been obese, although he did tote an extra 25 pounds on his 5’10” frame when he logged cubicle time for a Boston software firm. “I’d go backpacking for my vacations and notice that my clothes fit better and I felt better when I returned,” he says.
That realization gave rise to an entirely new category of backcountry guiding, and after a tough 2009-2010, Fatpacking’s lineup has rebounded to 18 trips this year. Silberberg will hit some of the world’s premier hiking destinations, including Israel’s Negev Desert, and he’ll scrape a modest salary doing what he loves: planning backpacking adventures and turning clients on to the outdoors.
He professes no magic formula or patented nutritional method. He goes light on lifestyle advice and eschews touchy-feely “love-ins,” as he refers to teary sessions of group psychotherapy. You hike, you camp, you eat. In fact, Silberberg encourages clients to eat as often and as much as they like. “I don’t run a sufferfest,” he tells me at our first night’s campsite, while whipping up an appetizer of fresh guacamole he’ll serve with blue corn chips. “Depriving someone who’s been largely sedentary and just hiked all day isn’t going to win any converts.”
That philosophy relieves my anxiety about Silberberg’s menu. Like many hikers, I’ve always believed that walking all day is a great excuse to chow down. But his initial signals suggested a backwoods version of The Biggest Loser. First, he discouraged us from packing our own snacks, not a single Fig Newton. Then, at a prehike dinner, he nibbled a plain lettuce salad and sipped unsweetened iced tea. And when I hoisted the group food bag? Well, let’s just say his groceries to feed seven hikers for three days felt lighter than what I’d carry on a two-person overnight.
Savoring a garlicky bite of avocado, I realize I won’t starve. In fact, I think, a bit of hunger might do me good. I’ve been fighting my own battle of the bulge, trying to shed a stubborn roll that’s accrued through overeating, too many late-night glasses of daddy’s little helper, a busted-ankle stretch of inactivity, and more writing about backpacking than doing it. Like many busy hikers, I hit the trail for a weekend here and there, too infrequently and fleetingly to realize the fitness gains Silberberg touts.
The cruel reality is that despite several decades of vigilant exercise (and an early ’90s job at BACKPACKER), I’m suddenly ballooning into average-American territory. According to the latest government research, the typical adult male in this country now weighs 195 pounds, up 22 from 1974; the average woman goes 165 and 21. From a low of 175 pounds, I’ve reached my all-time high and would love to lose 10 to 15. I can imagine a lot worse ways to get started than backpacking high above the Chihuahuan Desert on an oak- and pine-covered sky island.
Our first day on the trail delivers us into the sandstone core of Big Bend National Park. The six-mile hike from the trailhead at Chisos Mountain Lodge to our camp at Laguna Meadow was neither long nor especially difficult. All the same, a group decision to skip lunch on the trail after a giant breakfast means we’re keenly focused on dinner preparations.
“No meat?” asks Dan as he hovers over Silberberg, who is busy mincing and dicing ingredients for supper.
“Nope. Meat doesn’t keep, and I haven’t found a dehydrated version that’s any good,” says Silberberg.
“So that’s the secret agenda?” Dan asks. “We’re veggie-packing?”
Potential mutiny evaporates when Silberberg dishes out a delicious stir-fry of tofu, carrots, snow peas, broccoli, and garlic over brown rice. Surprising ingredients, eye-opening flavors, yet small portions. With the guac and chips to start and hot tea to follow, I’m full. Not stuff-my-face gorged, as I usually aim for when backpacking, but content. We’ll see how long this lasts.
“I guess this means we aren’t getting dessert, huh?” Susan mutters.
After dinner, Hennes goes from tent to tent gathering everyone’s trail mix, ostensibly for safekeeping in a steel bear box. During the day, we’re encouraged to munch from our personalized stores of nuts, dried fruits, sesame sticks, and assorted goodies provided by Silberberg (“Keeps your energy level constant,” he says), but it looks like midnight snacking is out of the question.
“Do you lock that thing at night to keep us fatties out?” asks Dan.
Size matters to Dan Shattuck. “I’m a big guy,” he says. “I’m built to carry heavy stuff and do hard work.” For the stocky 44-year-old with close-cropped hair and a ready supply of wisecracks delivered in a Minnesota lilt, physical size equals readiness. “Being big isn’t a point of pride, and I don’t lift weights, but my muscle mass allows me to be prepared if things come up,” he explains. Like removing window air conditioners at the 110-unit apartment complex he owns in Brandenton, Florida.
In Dan’s mind, there’s a line between big and fat, and he hasn’t crossed it. Not yet at least. “I’m not as fit as I should be, but I don’t consider myself fat,” he says. “I’m just a little heavy.”
Dan’s goal is to shed 20 pounds, an amount that has proven stubborn for good reason: He hates gyms and loves dining out. It’s not unusual for Dan and his wife to eat out five times a week. For a guy whose idea of a perfect workout is heavy exertion that yields a tangible result, the prospect of losing weight while backpacking with Silberberg sounded like just the ticket. “I get to see new things and tough it out?” he recalls thinking. “Sign me up.”
During a break at the South Rim, justly famous for a view that encompasses entire mountain ranges, the arc of the Rio Grande River, and a vast expanse of Mexican desert, Dan relates to me his personal history in pounds. Like many of us, he started out fit and slowly, ever so slowly, acquired more fat than is healthy or comfortable. In college, Dan was carrying 145 pounds on his 5’8” frame. When he entered the U.S. Army shortly after, he’d reached 160, a healthy weight for someone his height, according to the body mass index chart. “What’s crazy is I’m almost gaunt at that weight,” he says. (Since muscle is denser and heavier than fat, BMI numbers can be misleadingly high for fit athletes.) That wouldn’t be a problem for long. Too many MREs and not enough exercise while biding time in the Saudi Arabian desert caused an upward spike, to 175. “I actually gained weight during Desert Storm,” he says.
Back in civilian life, Dan continued to put on weight, but then resolved to reverse course. “I really started dieting. I was single and looking to date more. I got down to 165 pounds,” he says. He met his wife during this period (mission accomplished), made a killing in real estate, and watched the pounds creep back on. When he hit 206 last year, he started Googling for an adult fat camp.
As the waning sunlight streaks across the vast tableau at our feet, Dan pauses in his tale and seems caught in reverie. Perhaps a confession about using self-deprecating humor as a shield? Or a profound thought about the frustrations of finding a happy medium between prescribed and natural body weight?
“Man, a gin and tonic would be good right now, wouldn’t it?” he says.
When it comes to tracking calories, your body is like that annoying guy in accounting who catches the tiniest indiscretion in your travel expense reports. Every morsel in the mouth is carefully noted on an internal metabolic balance sheet registering intake versus output. If you’re like the average American, then each and every day you end up at least 20 calories over budget. Which means—come December 31—you’ll weigh two pounds more than you did January 1. That’s a big number if you maintain the same rate year after year, putting on 20 pounds a decade after you stop growing taller.
For a backpacker, those extra pounds are doubly insidious, as they’re both bad for health and bad for hiking (you’ll get more mileage out of that ultralight pack if you’re carrying less around the middle). Fortunately, backpacking itself offers a ledger-busting solution to the accounting problem. Duration and intensity make our sport uniquely efficient when it comes to weight loss.
On average, a 180-pound man carrying a 40-pound pack across steep terrain combusts more than 600 calories an hour while backpacking. (Calorie-burn numbers are approximate, and go up and down with body size, pack weight, and exertion.) By the minute, you can burn nearly twice as many calories running at a 7:50 per mile pace, but the average run lasts slightly more than half an hour. Long after the hares have showered and grabbed a snack, backpackers will still be out there striding, and burning, along.
On the Fatpacking venture in west Texas, we hiked at an easy pace for five to six hours daily. I typically go harder and longer, but even still I was vaporizing more than 3,300 calories. Add this to the 1,800 calories a man my size needs daily to power basic functions like breathing, digesting food, and maintaining a steady body temperature—all part of what’s known as basal metabolism—then factor in another several hundred calories for fetching water, strolling to the latrine, and wandering to an overlook, and the “calories out” side of the ledger was pushing more than 5,300 each day.
Calorie burn on that scale lifts backpackers out of the ranks of recreational duffers and thrusts us into athletically exclusive company, according to Neal Henderson, M.S., director of sports science at the Boulder Center for Sports Medicine. “Daily energy expenditure by a backpacker compares to that of elite cyclists, triathletes, and ultradistance runners,” he says. I’m not sure I’d want to see Dan or Jeff squeezed into spandex, but no one could deny they were Olympians at blasting calories.
The effects might not be obvious on a weekend trek, but play out a scenario of all-day backpacking over a week—or even months in the case of long-distance hikers—and the changes in body composition can be radical. That’s especially true when you maintain a normal diet on the trail. By Silberberg’s estimate, his clients eat about 2,500 calories a day. Which put me 2,800 in deficit—enough to burn 13 ounces of fat. Within days, I could actually detect my body geography shifting. My pants fit loosely in the waist.
Extended calorie burn alone doesn’t account for why backpacking is one of the ultimate pound-shedding, shape-altering activities. Our sport also taps body fat more efficiently than most alternatives. Runners, hikers, and other athletes all burn a mix of carbohydrates and fat. But the fuel mix is different. High-aerobic activities like running can burn an 80/20 blend of carbs to fat; the ratio varies widely for individuals, but in general your body depends on faster-processing carbs to sustain higher speeds. Backpackers, on the other hand, cruise along with about a 45/55 mix, our muscles consuming fuel at a rate more suited to slow-burning fats. In one study, researchers at the University of Birmingham found that maximal fat oxidation—28 grams an hour—is achieved, on average, at 62 percent of max heart rate. For optimum intensity, the university’s Asker Jeukendrup, professor of exercise metabolism, advises, “You should be able to talk without much effort.” Backpackers routinely operate in precisely this zone. Most of us go hiking for the scenery, of course, but when you run the numbers, the weight-loss benefits sure look good.
“Anybody want to finish off this tabouleh?” Joan Hennes holds open a zip-top bag full of salad. We had just climbed down from the summit of Emory Peak, the highest mountain in the park, and rewarded our peakbagging effort with a lunch of wraps filled with smoked Gouda, tuna, and sun-dried tomato. A bag of beef jerky makes the rounds, but nobody seems much interested in last night’s leftovers.
Dan waves her off. “I’m trying to lose some weight here,” he explains.
“OK, what are you craving?” Susan asks the group.
“I wish I was craving something,” says Dan.
Despite our self-imposed calorie deficit, hunger has not become the trip killer some feared. Partly, that’s because altitude and extreme physical exertion can suppress appetite in the first few days of a trip. And trail food, even flavorful meals like Silberberg’s stir-fry, is usually a far cry from what most of us eat at home.
My lack of hunger while subsisting on Fatpacker rations makes me wonder if other factors are at play. My stomach growled some, but why wasn’t I ravenous? After the trip, I consulted Michael Lowe, a leading researcher in the psychology of hunger. He says your stomach alone doesn’t dictate hunger. Lowe, a professor of psychology at Drexel University, points to two overlapping controls in the brain that govern how much we eat: the homeostatic and hedonic hunger systems. Homeostatic hunger is plain old empty-tummy hunger, and is activated by a drop in blood glucose. Hedonic hunger is an overdrive system triggered by the presence of food itself, or the pleasure it promises. Anyone who’s overindulged on Ben & Jerry’s understands hedonic hunger. “The look, smell, and taste of delicious food; negative emotions like stress; what people around you are doing—these are stimuli that evoke eating for reasons other than biological need,” says Lowe.
By extracting our group of Fatpackers from what obesity experts refer to as our “food environment,” by releasing us from work and home pressures, and by occupying our minds with a whole fleet of new sights and sensations, might Silberberg have tapped another benefit of backpacking that’s just as important as the calorie and fat burning? We’ve unplugged our hedonic hunger systems, leaving us to grapple with real, honest hunger and nothing else.
When I describe Fatpacking to Lowe, he sees its potential. “That could be an excellent way to lose weight. You have the absence of food cues, and the structure of eating has been handed over to a leader, so the decision to eat is less in your control,” he says.
Under the guise of backpacking with newfound friends in beautiful, remote locations, Silberberg puts into action all of the advice that Jane Brody, the Mayo Clinic, and countless other health nags wish we’d follow: limit portion size, dine on whole grains and vegetables supplemented with lean protein, drink plenty of water, avoid the empty calories in sugary beverages and alcohol, snack healthily, and limit sweet desserts. Add a mellow vibe, so it never feels like weight-loss boot camp, and you wonder when the reality TV show starts.
Our group’s discipline never wavers. Even when we stop at a convenience store in Terlingua while shifting venues from national to state park, they resisted the hiker’s sacrament: cold beer and Doritos.
Their perseverance pays off. When the Fatpackers line up for “after” measurements at trip’s end, the scale and tape reveal a lighter and tighter crew. Jeff, the military contractor, is the biggest loser. He dropped 10 pounds and reduced his body fat by 4.5 percent. Dan lost more than six pounds and shrunk his waistline by nearly four inches and his hips by two. Weight loss for Sarah and Susan was less pronounced, consistent with studies of thru-hikers showing that women are metabolically thriftier, but their bodies were reshaped nonetheless. Sarah, the nurse from Des Moines (and a former runner), has melted away more than four percent of her body fat while nudging up lean muscle mass. Her thighs are 3.5 inches slimmer and her waist more than three inches narrower. Susan, the New York financial analyst, shrunk her body fat by three percent while adding more than two pounds of muscle.
Jeff is all smiles and full of optimism: “What I did here isn’t the solution, but it may be the start of something.” Sarah is both hopeful and realistic. “This will help me. If I can hike with a pack for a week, I should be able to go out and run for three miles,” she says.
The Fatpackers will need all of that resolve and more to hold on to their hard-won gains. According to the National Institutes of Health, “most or all” lost weight is typically regained within five years. In fact, the more aggressive the initial weight loss, the likelier the rebound, says sports dietitian Nancy Clark, R.D. “Losing all that weight that quickly might seem like a great idea in the short run, but it’s counterproductive in the long run. The body is semi-starved, so once you gain access to food it will overcompensate. You’ll regain lost weight and even some more,” she says.
If the Fatpackers regress, they wouldn’t be the first backpackers undone by the withdrawal response. Online thru-hiker forums are filled with testimonials from lean, mean hiking machines who saw their weight loss wiped out in short order after reaching Katahdin, Manning Park, or some other personal mountaintop. There’s an obvious limitation: Backpacking all day doesn’t pay the bills. Sooner or later, you must reenter the world of convenience food, big-screen TV, and overbearing bosses. But leaving the trail needn’t mean saying goodbye to your trail-honed body. With some creativity and discipline—and regular return trips to the backcountry—the principles of Silberberg’s Fatpacking program can work at home (see “After Burn,” left).
My Fatpacking companions are proof of that. When I checked in with Dan, Jeff, Sarah, and Susan six months after Big Bend, their experiences were heartening. The trek had jump-started their efforts and given them a model for healthy eating and exercising. Sarah was running again and training for a 12-mile race. Jeff gained back only a few of his 10 lost pounds. Dan held steady at his new Fatpacker weight by stepping up his activity level through running, walking, and canoeing. Then he and his wife purchased a home in need of remodeling, a task he threw himself into. He dropped another four pounds. Plus, he rediscovered his love for backpacking and long dayhikes, and was making plans to join Silberberg on another adventure.
Susan’s was the standout story. She went on to lose almost 20 additional pounds after returning to New York, thanks to regular workouts and a meal delivery service that drops healthy, 400- to 600-calorie meals at her doorstep. “Before Fatpacking, I was starting to convince myself my metabolism had slowed down so much I would never lose weight again,” she says.
So how did yours truly fare? While I could only join the Fatpacking trek for five days, I still dropped one pound from my 186-pound frame while lowering my body fat by 1.3 percent, meaning I gained muscle while losing close to three pounds of fat. “I’d attribute your situation to a phenomenon I’ve seen in other fit athletes; they really don’t have too much room to improve,” explains Silberberg. (Yeah, right. Call me a “fit athlete” and I’ll believe anything you say.)
In the months after leaving Big Bend, my weight continued to drop as I practiced the portion control I learned from Silberberg and skipped the nightcaps. I reached 182, within sniffing distance of my target of 175, before the wheels came off. I ate nervously during a big deadline, then summer barbecue season arrived and, well, I’m back where I started. Fortunately, I already know the solution: I need to go backpacking.
Contributing editor Jim Gorman no longer packs energy bars, but won’t give up vitamin W around the campfire.