Ovi Magazine Issue #12: Sexuality Published: 01-03-2006

HoriZones
Biomechanics
International
By Nathan Hurst
It was the last home game of the season, and the Wisconsin Badgers had just been scored on and were now losing to the
Iowa Hawkeyes. The football announcer’s voice crackled across the airwaves preceding the Hawkeyes’ ensuing kickoff,
“Now kicking into the wind, we’ll see how strong Kyle Schlicher’s leg really is,” he said. But he was only partly right.
How far an athlete can kick a football,
or throw a shot put, or how well
he or she can perform almost any
event depends on much more than
muscle strength. Form, angle, physiology,
and biomechanics are hidden
factors that play important roles in
dictating how well an athlete can do
his job, and even how well a person
can walk or balance.
One of the areas these factors have
been used and studied is the therapy
of stroke victims, who often have
trouble walking. It now seems likely
that their problems are directly related
to the brain’s ability to control
muscle movement.
“For much of athletics, what’s more
important is control, how that force
generated by the muscle is regulated,”
said Kreg Gruben, professor
of biomedical engineering at the
University of Wisconsin-Madison.
Biologists have explored how nerves
connect muscles to the brain, and
how they cause muscles to activate,
but they don’t yet understand how
the nervous system controls those
actions.
“That’s why these factors are hidden,”
he went on. “We don’t know
how the control works.” The actual
mechanics are solvable using the
laws of physics, but Gruben’s work
attempts to go beyond combining
physics and biology, and reaching
into neurology as a way to understand
movement of the human body.
The problem was that he was in uncharted
territory. “What do we
know?” he asked. “I looked, and
what I had to do was back up and
back up and back up.” He started
with a simple action, walking, and
had to dissect it completely.
“To understand how people walk,
you want to understand first how
people generate force,” he said. In
the past, that meant observing the action
of walking and measuring everything
possible about it. That was
especially difficult because walking
is very complicated, with many different
muscle actions that a persons
brain must coordinate simultaneously.
So Gruben took a different
approach.
He isolated a simpler task involved
in walking. A seated subject would
push with his or her foot on a pedal
that measured both the force exerted,