In bobsleigh, luge and skeleton, collectively known as the sliding sports
crashes are an inevitability.
"... Tearing down the hill!"
"Oh my goodness!"
It's traumatic.
It's aggressive.
It's anything that is extreme times ten.
To think that somebody has gone to the Olympics without having had an episode like a crash
is very unlikely.
Christina Smith is a trailblazer in the sport of bobsled.
"...one of the most experienced drivers in the field..."
But in the years after she retired, she started to experience troubling symptoms.
Long-term, short-term memory loss, anxiety, fear, depression.
The inability to really stay focused and have emotional regulation.
Eventually, she was diagnosed with a traumatic brain injury
even though she’d never once been diagnosed with a concussion.
Just the fact that I was losing something of myself that I didn't realize
potentially could have been contributed to the affects of
the multiple runs, multiple vibrations,
the concussions that actually I'd never been diagnosed with my entire career.
There's growing evidence that, when it comes to the sliding sports
catastrophic concussions like the ones you get from crashing
might not be the main driver of brain injury.
Microconcussions are.
Concussions so mild they can often go unnoticed
and so common that they have a special name: sled head.
To understand how sled head happens, you have to know how concussions work.
Your brain is soft with a jello-like consistency.
Normally, it’s pretty well protected by layers of bone and tissue.
But if your head gets hit or shook around or just moves too fast,
your brain can shift inside its protective casing
bumping up against the sides of your skull.
When that happens, the fragile neurons that make up your brain can stretch or even tear.
And when they tear, they release toxins that can harm other neurons
triggering a chain reaction of damage, and leaving your brain vulnerable to further injury.
Concussions are serious and come with scary side effects.
But for the most part they heal with time and rest.
The problem is not all concussions are obvious.
Hey, if you got out of that sled and you're just a little bit dizzy
and then all of a sudden it's like,
"No, I'm good."
And you're full of adrenaline.
And essentially if you have the will and the desire
to get back up and dust yourself off and do it again, so be it.
But even a mild concussion is a concussion.
And if it’s not given time to heal, the damage can become more serious
and cause more enduring symptoms.
That kind of scattered brain and, you know, inability to focus.
So a lot of those little things...
It’s all those little things that make up sled head.
From the outside, sledding sports look smooth.
A graceful, if fast, run down an icy track.
But, inside a sled, things look and feel very different.
Sledding is, in a way, inherently brain rattling.
Even during the smoothest ride, a sledder is tossed about.
Shaken, bumped, whipped around corners.
It's so extreme that if you haven't gone to the bathroom
if you haven't blown your nose and if you haven't stretched
you have no idea what's going to happen to you.
There's a lots of bouncing and people moving quickly.
Their heads are going everywhere.
Peter McCarthy is a neurophysiologist
whose research focuses on how various forces effect our bodies.
He told me that sledding is a lot like a very, very intense roller coaster.
They're rickety and they've got lots of vibrations and they've got high g-turns.
G, as in g-force.
Roughly, the force of gravity or acceleration on an object.
Going for a stroll on earth, you’re experiencing 1 g-force.
Riding an average roller coaster, around 5.
Military fighter pilots average 9 gs.
And the average football player receives 103 gs when hit during a game.
The g-force of an average concussion is hard to measure or generalize
but one researcher found that most diagnosed ones have a g-force between 85 and 95.
And, when another researcher measured the g-force
of his own skeleton ride at the Whistler Olympic track
at its highest, here, he recorded 84.5 g-force.
That spike only happened for a few milliseconds.
But spikes like it can happen with every run.
And then there are the vibrations.
Long term exposure to vibrations can lead to a range of serious health issues
affecting basically all of your body’s systems.
There are even international guidelines
about how much vibration someone should encounter in a given period.
And when Peter attached devices on the helmets, sleds, and backs
of skeleton athletes to measure how much they were encountering
preliminary results showed that doing just one run
could potentially put you over the limit.
Sled Head is a phenomenon which seems to be neurological in nature.
And as a consequence ,we're thinking maybe vibrations are getting through into the brain
and that could be the cause of it.
All racing sports deal with both g-force and vibration to a certain extent
but normally they get dispersed throughout your body.
When you’re in a sled there's not much between your brain and the vibrations.
I was so close and low that I had
chips of paint and scratches on the side of my helmet from
just tapping going all the way down the track.
And so, you know, of course, I get out and I haven't had a crash or nothing would happen
but that just built up over time like a snowball.
Years after she stopped sledding, Christina went to a specialist
who ran a test called a quantitative electroencephalogram, or qEEG.
The beauty of this is that it can actually see where your brain is firing,
not firing at all, or partially or too much.
When doctors analyzed her results, they saw this:
roughly, the red shading correlates to over-activation.
In a brain that hadn’t experienced trauma those areas would be white.
It was like a a-ha moment for me.
It really highlighted, you know what I had been going through and I was no longer
hard on myself.
It was very common to overlook our own experiences because we're always about
the show must go on.
There’s only so much we can learn from one person’s brain scans.
Or the data from a few runs.
It needs an objective assessment of the discipline, basically.
Because if we just allow people to keep doing this
we don't know if it's safe for them to do that with the intensity they're doing it.
One way to better look after sliding athletes is to require them to wear a monitor.
A simple sensor system could detect an impact
and have that per person immediately flagged for treatment
and possibly sitting out until they've recovered fully.
And there are some exciting developments in tech
like virtual reality training that reduces ice time.
Or an FDA-approved collar that increases blood volume in your brain
giving it better cushioning.
In the future, new materials that could dampen vibration in the sled.
But the federation that controls sliding sports needs to make these available.
Or even mandatory.
And I feel that that's something that hopefully a way forward, though, who knows?
It depends on international bodies to make these legislative changes
and start looking at their athletes as actually things that keep the body alive.
The athletes are the lifeblood of any sport
and you need to protect them, in my mind.