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When it comes to shoes, there’s a lot that goes into picking just the right pair.
A fuzzy pair of slippers can keep you warm in the winter,
or your favorite flip-flops might just complete your beach-side look.
But have you ever wondered what a lifetime
of shoe wearing has done to your feet?
To answer that question, scientists are seeing what they can learn
from the non-shoe wearers throughout the world,
and what they’re finding might make you see your footwear in a new light.
[♪ INTRO]
One of the most famously barefoot groups in the world
are the Kalenjin people of Kenya.
If you’re a runner, you may have heard of Kalenjin athletes,
because they have dominated international races recently.
Which might have something to do with what it’s like to grow up as a Kalenjin,
since Kalenjin children are incredibly active.
These kids spend plenty of time playing outside,
and some run as far as 20 kilometers to and from school,
and usually, they’re doing all of that barefoot.
And it’s working pretty well for them, since kids who spend most of their time
barefoot end up building stronger, more flexible,
and more robust foot muscles than kids who wear shoes do.
Those buff foot muscles offer more benefits, too.
Barefoot kids are almost eight times less likely to
end up with lower limb injuries than shoe-wearers are.
Not only that, but going barefoot as a child may even
play a role in the shape of your feet, too.
When you see a human footprint, it typically looks something like this:
See that roundish gap there?
That’s the space left by your longitudinal arch,
or the natural bend upwards in the foot.
This arch helps us absorb shock and spring ourselves forward while running.
But some people’s footprints don’t really look like that.
Some of them look more like this, which means they’ve got flat feet.
See, some peoples’ arches can flatten under their own body weight,
which can lead to other problems later on.
And what’s interesting here is that all babies are born with flat feet.
Those arches only start to develop as those toddlers start to, you know, toddle.
However, if they don’t develop arches during childhood,
those flat-footed kids can have trouble walking or even have joint pain,
which is why pediatricians might take special notice of a kiddo’s foot development.
In the early 90’s, some orthopedists in India noticed that they weren’t seeing
nearly as many flat-footed children in their clinics
as was reported out of European or American clinics.
And none of them could recall a single flat-footed patient coming from
the rural communities; it was just the city kids who ended up with flat feet.
So, these doctors decided to conduct a study to figure out what was
so different about these two groups of kids’ feet.
As it turns out, it comes down to shoes.
See, the rural kids were much less likely to wear shoes on a daily basis,
and especially while playing, than the city slickers were.
And that made a big difference, since those barefoot kids
were three times less likely to get flat feet.
It turns out that the type of footwear they chose mattered, too.
Children who wore sandals were less likely to have
fallen arches than those who wore closed-toed shoes.
Most importantly, the team was able to pinpoint that the critical age
for arch development in children is before six years old.
But I’m willing to bet the majority of our viewers are over that age.
So if walking and running au naturel is better for our feet as children,
would it even matter if we ditch our Nikes as adults?
Well, the answer isn’t super clear cut.
There’s a contingent of athletes who say that barefoot is best,
especially for long-distance running.
Proponents claim it helps to reduce the impact of your foot hitting the ground,
thereby decreasing the chance of injury.
See, it’s about how you stick the landing.
Modern running shoes have elevated and cushioned heels,
which encourages you to land heel-first.
On the other hand—or foot—running without shoes has been found to encourage
landing on the ball of your foot, which generates less impact
up the leg and lets your ankle function as a kind of spring.
And a 2021 study found that daily activity in minimal footwear as an adult can
result in a roughly 50% increase in foot strength over six months,
which can lead to better balance and a healthier gait.
However, that’s not to say that barefoot running is totally risk-free.
It can put your feet in danger of short-term stress injuries,
which are influenced by factors like body mass and running technique.
One of the most well-documented risks deals with foot edema,
or excess fluid trapped within the tissues..
Basically, when you increase the stress on your feet,
they can end up swelling up a whole bunch.
And a hasty transition to running without that cushioned heel we discussed
earlier can be an effective way to shock your body into that response.
Apart from just making your feet puff up,
edema can cause a lot of pain and make running harder.
So the jury’s still out about whether it’s best for an adult’s running form
to kick their shoes to the curb.
But for us slower-moving folks,
shoes are probably still an okay choice for our day-to-day lives.
And, to be perfectly honest, most of us are probably not
giving up our fuzzy slippers anytime soon!
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[♪ OUTRO]