Are Canadians built different?

How snow-walking impacts the stabilizing muscles of the leg.

Those who have the luck to live in places that experience all four seasons know all too well the trials and tribulations of walking down an unshoveled sidewalk. Taking uneven steps as your ankles wobble and your torso twists to help you balance and avoid a cartoon-level slip.

We who have grown up in the winter weather — Canadians, Alaskans, Russians and Norwegians alike — are more prepared for what a walk to the grocery, or even the mailbox, might entail. Those with warm and sunny days year-round walk on sidewalks relatively less reminiscent of an obstacle course.

This year, the snow doesn’t seem to end in southern Ontario. As the municipality falls behind on shovelling, my morning walks have me wondering: Are the muscles in my feet and legs stronger than those in sunny climates?

So, I began my dive into the research.

Photo by Shawn Dearn on Unsplash

Your body is working overtime…

Here is what’s happening every time you walk down a icy sidewalk.

Healthy human bodies are remarkably good at walking. On flat surfaces, ours bodies manage two things simultaneously: the centre of mass (CoM) and the base of support (BoS). The CoM is the balance point of the body, while the BoS refers to the area beneath a person where the feet (or mobility aid) touch the ground.

The CoM and BoS are kept in check by three mechanisms: the step, the ankle, and the trunk. When walking, you might take a corrective step when you feel unstable, changing the BoS. Your ankle may rotate, changing how your foot applies pressure to the ground and shifting the CoM. Trunk movement changes where your centre of mass is through the hips and shoulders. These measures are happening all the time without you even thinking about it.

Snow changes the equation.

Dr. Aaron Best, a biomechanics and locomotion expert, and Dr. Amy R. Wu, a professor of Mechanical Engineering, set out to test how movements change when walking through snow in an experiment conducted in Kingston, Ontario.

When walking through snow, the body performs additional movements to compensate for a loss of balance. This includes the twisting or rotation of the ankles and the trunk of the body.

In young, healthy adults, they found that while snow-walking, there was increased compensation in forward/backward motion. But no significant change in how the body moved side-to-side. In other words, your body isn’t worried about falling sideways, but it is worried about braking.

On an icy surface, your brain subconsciously detects a slipping hazard. It then increases forward stability due to the perceived (and potentially real) lack of braking ability. So, it quietly kicks corrective actions into gear.

… and your muscles are keeping score.

Does your typical daily walk seem harder in the snow? Well, it’s not just in your head. Researchers have found that walking on uneven ground requires 27% more energy (metabolic cost) than walking on a smooth surface. That same study found an increase in leg stiffness when running on an uneven surface, a sign that the muscles surrounding major leg joints are ramping up their effort to keep stabilized.

Other studies have taken a look at what muscles are involved in speeding up and slowing down forward motion. A 2006 study found that the muscles involved in forward movement are also involved in bodily support. These include the quad muscles, glutes, calves and hamstrings.

The benefits of uneven terrain are real enough that researchers are looking to it as a rehabilitation tool. For people with Cerebral Palsy or those recovering from a stroke, walking on uneven surfaces may help treat stiff-knee gait — a condition where the knee doesn’t bend sufficiently during a step. Research has found that, when combined with other therapies, walking on uneven terrain can improve symptoms of stiff-knee gait. Specifically, it can increase the bend in the knee joint during stepping. This suggests that a snowy walk to the mailbox may be an unsuspecting therapeutic source.

So, are we built different?

Well… maybe?

We know that when we consistently work muscles, they begin to hypertrophy, or get bigger over time. But is 3-4 months of snowy mornings enough to cause growth? We know that navigating a snowy path demands more from your legs, but no one has published direct data on leg muscle development in people who live in snowy climates. That study, as far as I know, doesn’t exist just yet.

I started researching this piece fully expecting to find a clear answer, some type of proof that my lack of winter gymming is being made up by my daily commute. Instead, I have found something even better; the question remains, delightfully, open.

So, to my fellow Southern Ontarians, the sidewalks are still a mess, and the morning walks are becoming a game of “dodge the puddle” instead of “spot the black ice,” but at least the weather is getting warmer, and our legs are (maybe) stronger!