Week 1 Walk in the Cold The eighteenth-century walker and writer Elizabeth Carter claimed her favorite walks were those taken in "whistling winds and driving snows." Carter wasn't as unusual as we might think. Over the years, hundreds of walkers have expressed an enduring love for ice-blasted walks in the glacial depths of winter. In Christiane Ritter's astounding account of living in the Arctic Circle, she describes her daily walk in temperatures of -31°F: "I take my walk every day . . . in circles, ten times, twenty times, over the uneven snow drifts that have frozen as hard as steel." Walking to Lhasa in 1924, the explorer Alexandra David-Néel (who famously mastered the ancient meditative practice of thumo reskiang to self-heat) was stunned into enthralled silence by "the immensity of snow . . . an everlasting immaculate whiteness." Later, having trudged through miles of knee-high snow, she pronounced it "paradise." And yet for many of us, winter is the time we chose not to walk, preferring to stay home in the warm and dry. Big mistake! Decades after Carter, Ritter, and David-Néel embraced the cold, scientists are finally disentangling the extraordinary changes that take place in our bodies and brains when we spend time in moderate cold. Of course, ice, snow, and cold have been used to heal for centuries: Egyptian manuscripts refer to the use of cold water for reducing inflammation, British monks used ice as a form of anesthetic, and a nineteenth-century English physician called James Arnott used salt and crushed ice to reduce the pain of headaches and cancerous tumors. Fast-forward to Japan in the year 2000, and one of the first modern experiments to hint at the complexities of cold. Researchers identified two groups of female walkers: one group wore long skirts, covering every inch of leg, and the other group wore miniskirts, exposing their legs from ankle to thigh. The women agreed to wear the same skirts for a year and to have their legs regularly scanned. At the end of winter, magnetic resonance imaging (MRI) scans revealed that the legs of the miniskirted women had acquired an extra layer of fat. The legs of the long-skirted women, however, remained unchanged. This doesn't mean that exposure to cold makes us fat. Quite the reverse-as scientists were about to uncover. At the time it was thought that only hibernating mammals and babies carried a protective wrapping of brown fat, despite emerging studies implying that a few adults (outdoor workers in Scandinavia, for example) might also have pockets of it secreted beneath their skin. It was to be another decade before American researchers discovered the remarkable truth about brown fat-sometimes called brown adipose tissue (BAT)-the cold-induced fat acquired by the Japanese miniskirt wearers. In spite of its unfortunate name, brown fat is entirely free of the harmful lipids associated with excessive white or yellow fat. In fact, brown fat is a more effective fat burner than anything else, including muscle tissue, which might explain why thin, active people often carry more brown fat than their larger, more sedentary counterparts. But the most dramatic discovery came when researchers analyzed brown fat and found it packed with mitochondria, the tiny factories inside our cells that convert the food we eat and the oxygen we breathe into a form of energy called adenosine triphosphate (ATP). ATP supports every cellular process in our body. Brown fat exists to keep us warm and breathing (alive), which explains why a flash of cold spurs it into life-increasing our metabolism, regulating our appetite, improving our insulin sensitivity, halting the premature death of our cells. Brown fat achieves this by producing molecules called batokines, which help preserve us in multiple ways. For example, batokines appear to stimulate production of follistatin, a protein that strengthens our muscles. Batokines also increase a compound called IGF-1, which encourages growth in every cell we have, meaning (very simply) that our bodies are better able to repair themselves, and hinting at why a 2021 study found people with good stocks of brown fat were also less likely to suffer from hypertension, congestive heart failure, and coronary artery disease. No wonder scientists are hopping with excitement at the therapeutic possibilities of brown fat. Not only does brisk walking in cold weather keep our cells healthy and our bodies in trim, muscular shape, it also keeps our brains in good working order. Studies suggest that we think more clearly in cold weather than in hot weather. Our brains run on glucose, and when glucose is low, our brains become sluggish. We use more glucose cooling down than we use warming up, which could explain why some of us feel brain-foggy in hot climates but zingily alert in cold climates. A 2017 study from Stanford University found that people thought more decisively, calmly, and rationally in lower temperatures than in higher temperatures, reflecting a 2012 study that found warm weather not only impaired people's ability to make complex decisions but made them more reluctant to engage with the decision in the first place. We don't need to feel cold to experience enhanced cognition: merely looking at "cold" pictures makes our brains work with greater rigor. When Israeli researchers gave people a series of cognition tests interspersed with background images of either wintry, summery, or neutral landscapes, the participants achieved their best scores when they had the wintry images in their peripheral vision. Cold, in moderation, is also good for our mental health. A study of Polish students found that fifteen minutes in a chilly, leafless forest had "substantial emotional, restorative and revitalizing effects," implying that nature can make us feel just as rejuvenated in bare winter as in green-gold spring. Finally, a spot of cold appears to reduce feelings of stress. A 2018 report from the University of Luxembourg found that repeatedly applying cold to the necks of volunteers activated their parasympathetic (calming) nervous system, slowing and steadying heart rates-and raising the possibility that a judicious dose of chill could be more calming than one might think. None of this is to suggest we purposefully make ourselves cold and miserable. Instead, we should welcome the colder months as an exhilarating time to walk. The views are altered: who doesn't love the new vistas through sculpturally skeletal trees? Or the monochrome geometry of lines and shapes? Birdlife is more readily visible. Our brains are sharper, more zestily alert. Our beneficial brown fat is urged into action. To top it all, we build endurance: in lower temperatures, our hearts don't have to work so hard and we sweat less, meaning our bodies work more efficiently. Tips How cold does it have to be? Not particularly . . . Brown fat is activated in mild cold, around 61°F, according to Dutch physiologist and brown fat researcher Wouter van Marken Lichtenbelt. How long should we walk for? As long as suits, but one study found that two hours of exposure to moderate cold triggered the conversion of (bad) white fat (particularly in our stomachs and thighs) into (good) brown fat. Hate the cold? Numerous studies show that cold becomes less intimidating and discomforting the more we expose ourselves to it-a process called habituation. Wrap up warmly and increase the length of your walks bit by bit. Worried that cold air exacerbates allergies and asthma? A growing body of evidence suggests that winter exercise may do quite the reverse, reducing allergic inflammation in the airways and improving respiratory symptoms in many adult cases. Wear layers, so that you're neither too hot nor too cold. Hands, feet, and head are often the first to cool, as blood floods to our vital organs to keep them warm, so wear fleece-lined gloves, thick socks, and a hat. If you're warm enough, expose your forearms for vitamin D and your neck to activate brown fat (which often lies under the skin of the neck and collarbones, according to Ronald Kahn, professor of medicine at Harvard Medical School). Take a flask of something hot. We often get unknowingly dehydrated in cold weather. A flask of coffee will help activate our brown fat: caffeine, like exercise and cold weather, is thought to spur brown-fat production. Walking in deep snow can be exhausting, so consider snowshoeing-an excellent way to walk long distances through snow. Worried about slipping on ice? Ensure your footwear has the best possible grip/traction (check sites like ratemytreads.com). Walk slowly and sideways on steps and downhill. Use walking poles. Our arms help us balance and our hands can prevent falls, so keep your gloved hands out of your pockets. The cold is not a panacea, and hypothermia can kill, so wear the right clothes and footwear and walk as energetically as you can (see Week 2: Improve Your Gait, p. 10). Week 2 ImproveYour Gait when a youthful admirer told the French philosopher Simone de Beauvoir that he liked the way she walked, it was a compliment she never forgot. How we walk-our gait-provides a window into who and how we are. After Canadian researchers observed 500 walkers, they were able to identify (with an impressive 70 percent accuracy rate) which walkers had early cognitive impairment, reflecting previous studies suggesting that our gait at the age of forty-five can predict our chances of getting Alzheimer's. Merely by observing gait, explained Manuel Montero-Odasso-an expert in the relationship between mobility and cognitive decline-we "can help diagnose different types of neurodegenerative conditions." In other words, how we walk reflects how well our brain is functioning, hinting at what the future might have in store for us. Scientists don't yet know whether changes in our brain affect our gait or whether changes in our gait affect our brain. Either way, we need to pay attention to the way in which we walk. And yet how many of us do this? Putting one foot in front of the other, propelling ourselves forward, is the simplest and most natural of movements-one we master as toddlers. But it's also an act of unimagined complexity, involving balance, coordination, strength, and the firing of hundreds of neurons. When we walk, we engage almost every muscle and bone we possess, all of them synchronized in an extraordinary sequence of moves that no machine has ever been able to replicate. Our indoor laptop lifestyle is making it harder for us to walk with the effortless efficiency and grace of our forebears. Our bodies have lost much of their strength, balance, and suppleness, thanks to feet squeezed into fashionable shoes, days stooped over laptops, and evenings spent lolling on sofas. Meanwhile, our feet tilt, totter, and plod, their 159 bones, muscles, and joints barely used. Does this really matter? Arguably, yes. A poor gait compromises how we move, meaning we aren't experiencing the full freedom (and pleasure) that accompanies a smooth, flowing stride. Nor are we enjoying the full physiological benefits. Sports scientist Joanna Hall believes our current lifestyles are detrimental to how we walk. Sitting for too long has shortened and tightened our hip flexor muscles and encouraged our stomachs to slump. Crouching over desks and laptops has forced our necks and heads to jut unnaturally forward, stiffening our spines and restricting our back muscles. Leaning forward, for hour after hour, has weakened the small postural muscles that control the curve of our spines, leading to lower back pain. Meanwhile, walking in the wrong shoes has cramped our toes and stiffened the muscles in our feet so that we strike the ground with a flat plod (which Hall calls a passive foot strike ) rather than a springy rolling sole (an active foot strike ). And hitting the ground without using the splayed spread of our feet risks misaligning our pelvis. "We need to learn how to use the right muscles in the right way at the right time," she tells me as she puts my own walking style to rights. Hall-who has spent the last twenty-five years helping people walk as their bodies intended-recommends relearning how to walk in order to avoid injury and joint strain, and to enable us to pick up our speed and walk for longer. Research carried out by London South Bank University found that a month of walking with a full range of motion resulted in an accelerated walking speed and improved skeletal alignment. Hall's advice includes: Pushing off from the back foot, using the muscles at the backs of our legs. Peeling through each foot from heel to toe, using all of our toes to drive us forward. Lifting our ribs and lower spine to activate our abdominal muscles and create space in our core. Lengthening and straightening our neck, which frees our spine to move as we walk, while counteracting the stiffness that comes from long hours hunched over a computer. Swinging our arms freely from the shoulders, using our elbows to impel us forward-not in the manner of a 1980s power walker, but more as if our arms were a pair of smoothly jointed pendulums. Our hands should be loose, not bunched into fists. Medics at Harvard Medical School advise looking ten to twenty feet in front of you and lowering your eyes rather than your head when you need to check the ground (an upright head reduces the chance of neck pain). They also recommend swiveling the hips very slightly, saying "a slight pivot can add power to our stride," and taking care not to overstretch our stride, adding "concentrate on taking shorter steps but more of them." Of course you can walk in your own way, adjusting nothing. But, according to Hall, "getting our gait right reduces the chance of stiffness in our joints and spine." Harvard Medical School echoes this, saying that poor ingrained walking habits can be easily reversed ("with a little work") to avoid injury, to make walking both more beneficial for our health and more enjoyable. Getting our gait right means we can walk faster, should we want to. All walking is good-and in some circumstances slow walking is better (see Week 4: Just One Slow Walk, p. 18, and Week 42: Walk After Eating, p. 173)-but several studies suggest that brisk walking, around 4 miles per hour (or 100 to 130 steps per minute), brings extra benefits. A 2019 study found that brisk walkers lived longer than slower walkers, concluding that a faster pace meant "a lower risk of a wide range of important health conditions." Walking at a good clip means all our daily exercise can be accommodated as we walk to school, to work, or to the shops. Improving our gait also means we can walk for longer periods of time. Studies suggest that longer bouts of walking are particularly good for reducing body fat and improving mood. When we can walk effortlessly for hour upon hour, our opportunities for walking expand. We can hike long distance (see Week 36: Walk with a Pack, p. 148), walk pilgrimages (see Week 40: Walk Like a Pilgrim, p. 165), follow a river from source to sea (see Week 17: Follow a River, p. 67), or simply walk a route that we previously drove . Tips Consider your own walking style, making any adjustments and practising the suggestions above, taking them one by one. You should feel lighter and more upright, with a slightly accelerated pace. Ask a friend to check your gait, posture and alignment, or video yourself walking and make your own assessment. If you need help, look for walking coaches or tutorials online. Week 3 Walk, Smile, Greet, Repeat In 2005, the British psychologist Dr. Cliff Arnall declared Monday of the third week of January to be the saddest day of the year. A combination of bad weather, dark nights, failed new year resolutions and post-Christmas debt culminated - he claimed - in a day of universal and collective depression:"Blue Monday". Arnall urged us to think ahead to holiday time. I think a neighbourhood walk would be more effective. Walking exposes us to chance encounters with other people. Greeting others - neighbours or strangers - with a smile improves how we feel, both in mind and body, ensuring we return home happy rather than snappy, and gracious rather than grumpy. We don't need to exchange words - a smile is sufficient. Excerpted from 52 Ways to Walk: The Surprising Science of Walking for Wellness and Joy, One Week at a Time by Annabel Streets All rights reserved by the original copyright owners. Excerpts are provided for display purposes only and may not be reproduced, reprinted or distributed without the written permission of the publisher.
