Finding
the Right Balance
By
Alex Hutchinson
New
York Times, June 6, 2015
WE
all fall down. But while a tumble for a toddler is a learning experience, and a
stumble for an adult is usually just embarrassing, for older people it can be a
serious, even fatal, incident.
In
2010, 13 million Americans reported being injured in a fall, often caused by
simple trips on the sidewalk or on the stairs at home. For the over 65s, the
figures are worse: One in three in this age group falls every year, resulting
in some 250,000 hip fractures and more than 25,000 deaths, usually from
traumatic brain injuries. The health care cost of treating these falls is
estimated to be $34 billion a year.
But
if falling is such a common hazard, especially for older people, does that mean
falls are inevitable? Is there nothing we can do about it — like improving our
sense of balance?
Part
of the challenge is that balancing is trickier than you think. Most of us are
lucky enough that we rarely have to think consciously about it. But try
standing on one leg for 30 seconds, the way you might have to if a police
officer suspected you’d been drinking and driving. Then close your eyes, and
see how much harder it gets. That’s part of a sideline balance test if you’re a
football or hockey player and a trainer or doctor wants to assess whether
you’ve suffered a concussion.
I
discovered my own wobbliness a few years ago, while working on a magazine article
about high-altitude hiking. Researchers had shown that the number of balance
errors you make while holding a few simple 20-second poses — standing on one
foot with your eyes closed, for example — can signal the onset of altitude
illness. I tried the tests and found that, in the rarefied air of my Toronto
office (elevation: 249 feet), I was as unsteady as a Himalayan hiker with
mountain sickness.
As
someone who exercises most days, I found this unsettling: What was missing from
my regimen?
We’ve
come to view fitness as a collection of discrete traits — muscular strength,
aerobic endurance, flexibility and so on — that can be isolated, measured and
tinkered with independently. The pitfall of that approach is obvious: What is
strength or endurance worth without the balance and stability to use them in
the real world?
Simply
staying upright is, in some ways, a full-body exercise. You have fluid-filled
“organs of balance” in your inner ear that monitor the position and rotation of
your head; and there are sensors known as proprioceptors in muscles and tendons
throughout your body that detect subtle stretches and deformations. Your feet
alone contain 11 small stretch-sensing muscles: No matter how many calf raises
you do in the gym, your balance won’t be stable unless your brain is attuned to
the signals from these sensors. Even wearing socks interferes with this subtle
feedback and worsens your balance.
Walking
is trickier still, since each step is essentially a controlled fall. Last year,
researchers from Ohio State University showed that they could predict with
accuracy where a walker’s foot would land by looking only at the trajectory of
the upper body during the previous stride. What seems like a simple act, in
other words, is actually a complex and near-instantaneous calculation that
enables you to place your foot in exactly the right spot to prevent a
faceplant.
The
current approach to this challenge is to add an additional box to check off:
balance training. United States health guidelines already suggest balance
training for older adults at risk of falls, and European countries like
Austria, Ireland and Denmark recommend it for all older adults.
A
step in the right direction, you might say, but it still presents balance as an
isolated practice. The evidence is that a more integrated approach has greater
benefits.
For
an older adult who wants to continue living independently, it’s clear that the
ability to rise from a chair and walk across the room, which requires the coordination
of muscle strength, balance and aerobic activity, is more important than any
individual element of fitness. And it’s not just a physical challenge. One key
warning that you’re at higher risk of falling is if you tend to stop walking
when you talk — a sign that the cognitive demands of staying on your feet are
overloading your brain.
An
emerging body of research suggests that exercising in a way that taxes your
coordination, agility and balance — a suite of abilities known as “gross motor
skills” — rewires your brain in ways that are fundamentally different from
straightforward aerobic activity or strength training. By improving these
physical attributes, you also enhance cognitive performance.
One
such study, published in
2011 by neuroscientists from Jacobs University Bremen in Germany,
involved a yearlong trial of 44 older adults that compared the effects of
walking three times a week with what they called “coordination training”: a
series of exercises using stability boards, balls, jump ropes and other
equipment, and including elements like “reaction to moving objects/persons.”
Superficially,
the two regimens were equally good: Compared to a control group that did
stretching and relaxation exercises, both groups boosted their performance to a
similar degree on cognitive tests, including measures of perceptual speed and
executive control. (Other studies have produced similar findings using a range
of coordination and balance exercises like obstacle courses, tossing balls into
baskets and learning to juggle.)
But
what’s interesting is that the cognitive gains occur in different ways
depending on the mode of exercise. While aerobic exercise and strength training
trigger brain chemicals that enhance neuron growth and survival, balance and
coordination call on higher-level cognitive processes that seem to increase the
number of synapses connecting the neurons.
That,
in turn, suggests another reason simple balance exercises alone won’t achieve
what we want. It is novelty and unpredictability, rather than repetition, that
are essential to keep your brain engaged. A recent study
by researchers in Denmark, Finland and Germany compared a group of
15 endurance-trained athletes, like runners and cross-country skiers, with a
group of skill-trained dancers, gymnasts and figure skaters. The researchers
captured data to assess their subjects’ “motor cortex plasticity,” a measure of
the brain’s ability to change its wiring in response to new stimuli.
Both
types of athletes have highly trained calf muscles, but endurance athletes use
them repetitiously, in a way that the brain consigns to autopilot. Sure enough,
plasticity in the area of the brain that controls calf muscles was no different
between endurance athletes and nonathletes. In contrast, the dancers, gymnasts
and skaters, for whom autopilot is not an option, showed dramatically higher
plasticity: Their neurons were primed to keep learning new motor tasks.
A
striking feature of the balance and coordination exercises used in these
cognitive studies is that they sound a lot like games. Whether you’re dancing
or playing tennis, the unpredictability of your partner’s actions means that no
two workouts are the same. Perhaps the enjoyment we get from a good game isn’t
just a nice bonus: It’s an indicator that we’re fully engaged, mind and body,
in the activity. You could call that achieving good balance.
