Not too long ago, people climbed mountains and trekked thousands of miles through every manner of climate without the help of fancy wearable tech, personalized temperature control, or advanced gear. Today, such a thing is unimaginable.
For Scott Carney, that’s a big issue. In his recently released book, What Doesn’t Kill Us ($27; Rodale Books), he explores how our widespread adoption of comfort-enhancing technology has affected our health. Deprived of exposure to the extreme—temperatures, stresses, discomfort—our bodies lose the ability to adapt. Our biological strengths, skills, and critical functions go to waste because they’re no longer cued by our surroundings and put to use. In short, Carney writes: “effortless comfort has made us fat, lazy, and increasingly ill in health.”
Despite some initial skepticism, Carney ultimately becomes an advocate for Dutch survivalist Wim Hof’s extreme practices—think freezing water baths and barefoot snow races to make us more efficient at burning energy—as the antidote to our temperate lives. But he also offers other, more realistic ways to exploit our untapped biological powers.
You Don’t Need to Upend Your Entire Life
Carney added only colder showers, breathing exercises, and breath-hold push-ups to a routine that primarily consisted of casual outdoor runs a few times a week. After six months, he lost 38 pounds and five inches off his waist, was able to run harder for longer during his fitness testing at the Boulder Center for Sports Medicine, and shifted his body from favoring carbs to burning fat as fuel.
Start Moving Before Breakfast
First thing in the morning, your body “hasn’t yet been weighed down by the process of digestion.” As such, it’s primed to be its most responsive to efforts to reset your metabolism and blood flow. If you’re not an early exerciser, don’t sweat it. Just a few deep and held breaths to clear out CO2 and replenish your systems with the maximum amount of oxygen or a couple yoga stretches will have a meaningful impact over time.
Turn Down Your Thermostats
Learn to love the cold. Thanks to climate control and highly efficient layers, we live in an “eternal summer.” As a result, our bodies no longer experience “metabolic winter,” an important evolutionary stage where the body has to adapt to discomfort. Carney’s thesis, increasingly supported by emerging science, is that this “cocoon of consistency” contributes to global epidemics of obesity. Try running outside in minimal layers (although a hat and gloves are fine to protect extremities) and dialing back the thermostat so you feel a little shiver throughout the day.
End Your Shower on a Cold Note
The bulk of your rinse can be warm and comfortable, but tack on one minute of cold water at the end. Your body will gradually handle longer and colder showers, a sign that you’re successfully resetting its definition of “normal,” which will affect the way your body uses energy and handles extreme temperatures.
Make Time to Meditate
You have limited energy. Don’t let a stressed-out brain consume it all. While Carney found visualization to be the most effective way to quiet his mind, most meditative practices will do. A calmer mind lets your whole body function more efficiently.
During Summer, Run Outside at Noon
Or whenever your route will be close to its hottest. This principle of “active conditioning” applies just as readily in the warmer months as it does in the dead of winter. Forcing your body to perform in uncomfortable circumstances prevents it from getting too used to one environment and growing weak or inefficient.
Use a Paper Map
Leave the apps and GPS at home in favor of an old-school map. Carney recounts a study showing that going analog has proven to enlarge the volume of the hippocampus—the part of the brain responsible for emotion and memory—as long as it’s practiced repeatedly. Once you stop that practice, your hippocampus will start to shrink again. While this trick may not help your athletic performance, it emphasizes a major tenet of Carney’s work: that certain biological strengths will lay dormant if they aren’t exercised. (And, hey, it might come in handy next time your phone dies on a long, winding trail run.)
Obstacle Course Races Are Great Training Tools
Whether it’s a Spartan, Tough Mudder, or Europe’s (and Carney’s) favorite, Tough Guy, the real challenge of obstacle course racing is mental. Once you “overcome your natural instinct to curl up into a ball and wish for home,” you’ve effectively conditioned your body to push its self-imposed limits. This shift mimics the end goal of Carney’s (and Hof’s) program, and thus presents a good opportunity to try it out yourself.