Feet, Shoes and Science
There is one area of advertising-based bull-plop that very few members of the public—actually I’d go so far as to say, few members of the scientific community, too—are really aware of. Big companies that have hoodwinked us all; they’ve fed us lies about our own bodies, and for decades we have blithely stood there and said “Ooh, what a shiny new product, I want that one!”
But, before I get onto that, I want you all to do me a favour, and participate, get involved, get up out of your computer chair/beanbag/bed/spot on the floor, and go for a walk; just a quick walk, around your room/office/outdoor-wifi-connected area. Pay attention to the way you move, as you do so. Try not to make your movements too deliberate, but remind yourself what walking is like.
Hopefully this is not how you were walking
Okay, have you done that? Good. So, you may have noticed what human biologists would call a “heel-strike striding gait”. It’s how we, as humans, move about.
Heel strike locomotion
Now, I’d really love it if you’d do me another favour—this will work best if you’re wearing running shoes. So, if you’re really into running, they might look like this:
Reebok Zigtech shoes
...or, if you’re not so fond of running, they may look a little more like this:
These look like they've seen better days
Personally, mine look like this:
My shoes have seen better days, too
If you are not wearing running shoes, a patch of soft grass should work, instead. Do a little run. You don’t have to get your heartbeat up; you don’t need to make yourself puffed or sweaty. Just run a little. Run the way you would if you were in a race, running late for the bus, escaping from a mugger. Go.
Great. So, did you find that your running was much like walking, but faster? If you’re like most people, then your running style will also involve a heel-strike striding gait. That’s why it feels comfortable to run in big cushy sneakers, like these:
Nike Turbo shoes
They absorb all of the impact of hitting the ground, and bounce you back up and on your way. Well… make it feel like they’re absorbing all the impact, anyway. For the last forty or so years, companies like Nike, Adidas and Reebok have been making bigger, better, bouncier shoes, with chunky heel wedges to absorb that force.
So, why is it that running-related injuries are increasing? Well, obviously it must be because those shoes are making running easier and better for everyone, and if more people are running, then more people will get injured.
Not necessarily so. While the shoes stop the amount of force the sole of your foot is taking, there is still a whole lot of force wearing down your joints. Heel striking as a running technique is not like homeopathic medicines, multivitamins and acupuncture that have been sold to the public, whilst skeptics stand back and wonder how marketing can be so effective. No, heel striking has pretty much everyone convinced. That’s just how we run, isn’t it? And the big, cushy shoes protect us while we do. There would be more injuries without them…. right?
I know I’m pushing it, but could you do my one last favour? Take off your shoes, find a gravelling bit of road, or path with some stones in it; something that you wouldn’t normally want to run on, and have a go.
These photos are of two Kalenjin runners from Kenya, a barefoot 12-year-old girl (left) and a boy of the same age in running shoes. Note the differences in foot angulation as the girl prepares for a forefoot touchdown and the boy prepares to land heel first. (Photos from nature.com original images: D. E. Lieberman.)
When you run barefoot on a hard or uneven surface, you find your forefoot will naturally point downward, as you place the ball of your foot on the ground. Then your ankle bends, your heel strikes the ground last, if at all. And that way you save from hurting your feet. Instead of your heel, joints and bones taking the force, your muscles take the force. This means your muscles have to work, when ordinarily they would not. The difference is that sore muscles will repair themselves. Muscles get bigger and stronger. When you wear down your bones and joints, you get cartilage injuries, inflamed tendons and stress fractures. There are studies, which show the differences between the forces involved in heel strike running and forefoot running. Harvard’s Dr. Daniel Leiberman is at the forefront of these studies, and has some insightful points to make on the topic.
Unfortunately science doesn’t get far without someone cashing in. After all these studies to show that we don’t need big shiny shoes made by the most profitable companies, we’re seeing the emergence of new companies, selling slim, shiny “barefoot” running shoes. Kinda defeats the purpose if you ask me.
So, what am I really trying to say to you? Basically, what I am getting at is that heel-strike running is not necessarily a great idea. It’s energy efficient in the short term, but it increases the risk of injury. Then why do we do it? Well, studies suggest that we don’t do it naturally. Just like how you stopped heel striking when you had to run barefoot on a hard surface, groups of people who have been kept away from westernised marketing still use the forefoot running technique—something that our ancestors probably used to hunt and gather, long before the concept of modern running shoes and sports science came to play. If you can handle the overly journalistic writing style, I recommend having a read of Christopher McDougall’s Born to Run. It certainly does make my feet itch to go running.