30 | New Scientist | 17 August 2019
Book
In Praise of Walking: The
new science of how we walk
and why it’s good for us
Shane O’Mara
Bodley HeadWHEN a sea squirt settles on
a home, it never gives another
thought to going out. In youth,
squirts are constantly on the
prowl, swimming in rock pools
and hunting for prey. But once
an adult finds suitable real estate,
it permanently attaches to the
stone, consumes its own spinal
cord and brain, and spends its
remaining days capturing
whatever nutrients float by.
According to neuroscientist
Shane O’Mara, this life cycle is
perfectly sensible. “Brains have
evolved for movement,” he writes
in In Praise of Walking. “If you’re
going to be stuck... with your food
all around you, then why do you
need a costly brain?”
O’Mara uses the sea squirt
and similar creatures to evoke
the essential connection between
walking and cognitive activity in
humans. From his perspective,
mobility is one of the defining
qualities of animals including
Homo sapiens, and the sessile
lifestyle of the modern couch
potato is dangerously unnatural.
The benefits of taking to our feet
could easily fill a book, and O’Mara
does devote whole chapters to
them. The physical benefits are
well known: cardiac health,
muscle development and
improved digestion. The cognitive
gains are less well known but at
least as dramatic.
Take the Stroop test, a standard
measure of cognitive control in
which the word for a colour is
written in a different hue (“red”
written in green ink, say) and theNothing like a good walk
Walking, or even standing, makes us fitter and smarter. It also
helped us colonise a whole planet, finds Jonathon Keatssubject must name the ink colour
as fast as possible. Mismatched
stimuli tend to slow people down,
especially when asked to perform
other tasks simultaneously.
But as O’Mara explains, a 2017
study by David Rosenbaum, a
psychologist at Tel Aviv University
in Israel, showed that standingup significantly improves
performance. “It is as if the mere
act of standing mobilises cognitive
and neural resources that would
otherwise remain quiescent,”
writes O’Mara. Other recent
studies show that blood flow to
the brain increases with walking,
and this alters the brain state as
it calls on greater cognitive
resources, “constituting a call to
action as well as... to cognition”.Views Culture
SIMONKR/GETTYOne legacy of this activity is
the knack for moving in groups,
whether as soldiers on the march
or as an army of protest. Another
is our remarkable efficiency as
walkers, and O’Mara cites a recent
study that measured walking
efficiency using exoskeletons.
It showed that humans intuitively
expend as little energy as possible.
Unfortunately, the effect of
covering so much territory, often
in passing, doesn’t help the book
overall, as O’Mara has a tendency
to ramble. That and a sometimes
pedantic writing style aside,
In Praise of Walking is both
informative and persuasive
enough to rouse the most ardent
couch potato – perhaps saving
humanity before our lifestyle
consumes our brains completely. ❚Jonathon Keats is a conceptual artist
and experimental philosopherIn the interest of praising
walking as roundly as possible,
O’Mara seeks out the big picture
as he considers, for example, the
mechanics of walking – a rhythmic
action underlying motion and
balance. This has a genetic basis
dating back at least 420 million
years, revealing an evolutionary
relationship between walking and
swimming. At the opposite end of
the timeline, he considers the
walkability of cities and proposes
improvements to urban planning.
O’Mara is especially keen to
show how walking made us what
we are today. The morphological
changes that allowed us to stand
upright – including alterations to
the skull, pelvis and feet – freed
our hands for foraging and
carrying babies. But the biggest
impact was on migration. The way
we walk is adapted to endurance,
making us “possibly the best
walkers of all species”, he writes.
By radiating out of Africa on foot,
we eventually colonised most
continents and habitats.Walking offers us
an enormous set of
evolutionary advantages“ The way in which
we walk is adapted
to endurance, which
may make us the best
walkers of all species”