Walk Like A Penguin

Tablet Infographic's intermittently viral advice on How to Walk on Ice:  www.tabletinfographics.com/#/ice/

After a month of record-cold temperatures here in Chicago, we’re finally beginning to thaw out. Almost as if to celebrate, an infographic appeared on one of the Alexander Technique Facebook groups with advice on how to walk on ice. On the left, the graphic shows how walking on ice with the front foot forward increases the risk of falling. Whereas on the right, there’s a penguin. Wait a second: a penguin? We’re supposed to learn how to walk on ice from a PENGUIN?

Since seeing this infographic, I’ve been doing almost nothing else but reading about penguins and watching penguin videos. Maybe I shouldn’t be taking a penguin image so seriously. But I’ve become obsessed with what it says about the state of modern humanity that an infographic about walking on ice takes cues from a penguin.

Ladies and gentlemen, Exhibit A:

This is not to diss penguins. Penguins are wonderful creatures. They have, unlike other birds, evolved to swim with extraordinary agility. Emperor penguins, to give one example, will launch themselves from the water onto the ice to avoid predators (like the truly terrifying leopard seal).

But on land, penguins are TERRIBLE at walking—penguins expend twice as much energy on land as any other terrestrial animal of the same size. Penguin legs are short and their feet are big. While longer legs would help a penguin walk more easily, it’s thought that long legs would also lose heat too quickly in the harshly cold environment in which many penguin species live. Waddling looks comical, but it turns out to be the best way to walk if you have really short legs.

In contrast, almost every aspect of the human body has evolved to facilitate efficient walking. Our long necks and tall narrow waists allow the head, ribs and hips to move independently from each other, facilitating the pleasing spiral swing of a healthy walk. The curve of our lower backs—the lumbar spine—positions the torso directly above our pelvis and legs, rather than pitching our torso forward, like in our closest cousin, the chimpanzee. Our human pelvis—the illium—faces sideways and our knees are angled underneath our hips. This allows us to balance our weight on one leg while keeping our trunk upright. And we have a large heel bone—the calcaneus—and well-supported arches, that allow us to roll through the foot and push off the front toes.

Human beings as a species may not be as adept at swimming as penguins, but we are much, much better at walking.

Human adaptations for efficient walking. This image has been modified from Lieberman's The Story of the Human Body to include, um, a penguin.

It’s particularly bizarre to look to penguins for help with staying stable on ice because there’s so little consequence for a penguin when they slip. It’s one of the delights of watching penguin blooper reels that they fall without injury—even from a significant height. And a penguin falling on its belly introduces another form of locomotion—tobogganing

In turns out that an animal’s size and its danger of injury in a fall are linked. An animal the size of a mouse, amazingly enough, can fall any distance without risk of significant injury. My 15 lb cat has swiped a bug off the ceiling from a high shelf and then leapt the 10 feet to the ground with little concern. A 40 to 80 pound emperor penguin can trip without fear. But adult humans aren’t so lucky. Any animal above 100 kg (220 lbs) will be at serious risk for injury from a fall of just its own height—picture a horse, cow or elephant. While adult humans weigh less on average than 100 kg, we are quite tall for our weight. Adults can break bones just from tripping, and falls are the leading cause of fatal and non-fatal injuries in seniors above the age of 65. 

To help keep us from falling, we have rescue (or righting) reactions. These are automatic—though most likely learned—reactions to keep an animal from overbalancing. Rescue reactions have been studied in many animals—cats and dogs seem to be the popular laboratory preparations. (Even bats have been studied—though since they sleep upside down, they do not share the same righting reactions common in other mammals.) Rescue reactions in humans are very robust, triggered by information from multiple senses: not just the inner ear (vestibular system), but from the eyes, head balance, sense of body position (proprioception) and touch (such as the contact of the feet on the floor). There are many rescue reactions, from staggering and bracing the legs, to sweeping the arms. “If the limbs are trapped, the trunk will be moved so as to take the impact on the shoulders,” balance researcher TDM Roberts tells us. “The movements are organized as though to avoid impact with the skull at almost any cost.” 

Rescue and righting reactions are studied in the laboratory in many ways, including putting subjects on a "tilt-table." The image is from TDM Roberts Understanding Balance, p. 163.

In December of last year, I experienced my rescue reactions when I stepped on a sheet of black ice walking home from a gig. At the moment my foot began to slip, I felt my arms shoot out and my legs brace of their own accord. I stayed on my feet. I felt particularly lucky because I was more encumbered than usual. I was carrying my violin on my back, my courier bag over my shoulder with my girlfriend’s laptop in it, and a grocery bag with a pyrex that had contained my dinner. Disaster averted.

So if we’ve evolved to walk well and we have well-ingrained rescue reactions, why do we need a tutorial on how to walk on ice? Obviously, winter is dangerous and ice is slippery. But winter is dangerous partly because our built environment is so safe.

Two winters ago, Kyra was leaving the morning after one of those wintry-mix storms that leaves equal parts snow, slush and ice on the ground. She strapped her cello to her back and stepped out on to the front porch with extra caution. But when she reached the stairs, she went flying, not because she wasn’t prepared for the slippery stairs, but because she didn’t expect the hand-rail to be covered in ice as well. She was lucky. Though she landed on her chin, she suffered only minor bruises. She also provided another instance towards a possible hypothesis: that musicians modify their rescue reactions to protect their instrument first, their own heads second.

My near slip in December was a similar point. The black ice was hidden in the shadow of a street lamp. The rest of the sidewalk was clear. The situation was only half-safe, but I expected it to be completely safe, so I nearly fell. This is true of much of our modern environment: an expectation of safety brings with it inattention and complacency. (There’s a similar effect in roadway construction—boring flat roads are more dangerous than dangerous swervy roads because people drive more safely on dangerous swervy roads.) 

Is there one best way to walk on ice? Tutorials on the ‘correct way to move’ are a byproduct of standardization, only sensible in a manufactured landscape. Better to think of unlearning our habits—trading the one wrong way not for the one right way, but for the ability to choose from many possibilities.

With enough time, such modern conveniences can actually change our bodies and our reactions. Researchers in Europe have found that seniors who have lived their lives in cities with cobblestone streets are less likely to fall than seniors who live in cities with smoothly paved streets. Cobblestones are more precarious, they demand attention and adaptability.

Our habitats create our habits. Before studying Alexander, I walked as if still slumped in a classroom chair: head forward, upper-back leaned back, hips forward as if about to “limbo.” Many people walk like this, or in some other strained way. 

The problem with such habits is that they it become our default way of moving, whether the sidewalks are icy or the sidewalks are clear. Looking back on my near fall in December, I wonder: If I still walked with my hips pushed forward, would I have slipped on the ice? It's hard to say. But walking with your hips forward—already out from under you—is a fall waiting to happen.

So is there one best way to walk on ice? Tutorials on the “correct way to move” are a byproduct of standardization, only sensible in a manufactured landscape. Better to think of unlearning our habits—trading the one wrong way not for the one right way, but for the ability to choose from many possibilities.

I went for a walk this morning down to Lake Michigan, about a mile from my apartment. For most of the way I had little choice but to follow the sidewalk. Trucking along the cement ground, I could experience simple walking, my bipedal inheritance in action: the free balance of my head on my spine, the swing of arms and torso over my hips. I could experiment with walking that was a gentle fall forward, or mix it up and bring my attention to the thrust of my toes from behind.

When I got to the lake, though, I left the sidewalk. Even in flat Chicago, the parkland is gently rolling. The ground is uneven. Most all of the snow had melted from the slight rise overlooking the lake. My feet sank into the muddy ground at odd angles. Though I was still walking, my gait was as changeable as the terrain—here stepping around a puddle, here high-stepping my knees over an unmelted chunk of snow, and once, yes, swaying from foot to foot over a patch of ice, like a penguin.


Thanks to Alexander Technique teacher Jennifer Roig-Francolí for sharing the How to Walk on Ice infographic. I turned to Daniel Lieberman's The Story of the Human Body for a guide to human adaptations for walking. The relationship between animal size and risk of injury in a fall comes from Steven Vogel's Life's Devices: The Physical World of Plants and Animals. Rescue reactions are described in TDM Robert's Understanding Balance. Studies on falling on the cobblestone streets of Europe came from the Blakeslee's The Body Has a Mind of Its Own. And the tidbit about drivers driving more safely on more dangerous roads is found in Tom Vanderbilt's Traffic.