muggy and windy
mississippi river road north
Was able to get in a quick run between thunderstorms. It’s funny how the winter weather didn’t prevent me from running outside, but these spring thunderstorms are. So humid. At one point during the run, when the walking path dips down and follows alongside the wooded gorge, everything looked weird, almost like I was seeing it through a filter. I wondered if it was my vision then I realized it was steam, trapped in the trees! Yuck.
Before and after the run I worked on having more fun with medical terms. Specifically, more fun with the biomechanics of walking. So much fun! When I started it, I had no idea where it would lead me. This is the unexpected result:
It starts with a step, versions and variations
“Where does it start? Muscles tense. One leg a pillar, holding the body upright between the earth and sky. The other a pendulum, swinging from behind. Heel touches down. The whole weight of the body rolls forward onto the ball of the foot. The big toes pushes off, and the delicately balanced weight of the body shifts again. The legs reverse position. It starts with a step and then another step and then another that add up like taps on a drum to a rhythm, the rhythm of walking (Rebecca Solnit, Wanderlust).”
It starts with a step:
heel touches down
weight rolls forward
onto ball of foot
big toe pushes off
step + step + step + step + step + step + step = walking
The biomechanics of a step: The Stance Phase in 5 parts
- Heel strike/the heel first touches ground
- Early flatfoot/from when the foot is flat until body’s center of gravity passes over foot, here the foot is loose and floppy
- Late flatfoot/body past center of gravity, heel beginning to lift, foot is rigid
- Heel rise/the heel rises off the ground
- Toe off/the toe lifts off the ground.
the heel strikes
on the ground,
not out at the plate or
because of unjust working conditions.
a police officer with a morning shift.
another officer, working the night shift.
apparently I was wrong about why the heel was striking.
It is because of unjust working conditions.
She and other foot workers are refusing to lift anything off the ground until their demands are met, namely adequate health care.
They are rising up!
Management is becoming increasingly irritated by the peaceful strikers.
All mechanical operations have been shut down.
How can the toe be lifted off the ground when the heel won’t do her job?
The early and late flatfoots, who have both finished their shifts, are called in to force the heel and her compatriots to submit.
Neither of them are happy about it.
They’re tired and want to go to bed.
Besides, they agree with the heel and are angry with management.
The biomechanics of a step: The Muscles
During the heel strike/early flat foot phase the anterior compartment muscles work to gently lower the foot onto the ground. The anterior compartment muscles are the tibialis anterior muscle, the extensor hallicus longus, and the extensor digitorum longus. .
During the late flatfoot to heel rise phase the posterior compartment muscles control the body so it doesn’t fall forward. The posterior compartment muslces are the gastrocnemius, the soleum and the plantaris.
During the strike, the heel is confronted by some well-meaning but naive co-workers who are urging her to reconsider her tactics. “Why not ask nicely?” the tibialis anterior muscle suggests. “Yes!” agree the extensor hallicus longus and the extensor digitorum longus, “if we take a gentle approach and try to reason with them, management is sure to see that we deserve better!”
Listening in on their conversation, early flatfoot rolls her eyes and can be heard to mutter dismissively to late flatfoot, “yeah right.”
Heel refuses to listen to the anterior compartment muscles. “We will strike!” she declares. She is joined by many others, including the posterior compartment muscles. The gastrocnemius and the soleum help by reassuring the crowd of striking workers and the plantaris delivers the strikers’ demands to management.
The biomechanics of a step: The Swing Phase in Three Parts
- early swing/after toe is off the ground, just until it is next to opposite foot
- midswing/the swinging foot passes by the opposite foot
- late swing/lasts from end of midswing until heel strike
The striking heel, along with the toe and the ball of the foot, soon realize that their tactics are not working. Management is refusing to consider their demands. They reluctantly determine that their only option is to walk out. To do this, they need the help of the other foot. The dorsiflexors of the ankle joint are enlisted to initiate the swing phase so that the toe can try to convince the workers in the opposite foot to collaborate on the direct action. The big toe is successful with her negotiations. So successful that not only does the opposite foot agree to the plan, but so do early and late flatfoots. Slowly and steadily the feet trade off steps. One heel strikes, one foot is flat, one toe lifts off. The other heel strikes, the other foot is flat, the other toe lifts off. Step. Step. Step. Step. Step. Step.
note: The technical information for the versions comes from these sources:
I had not intended to write about the heel striking, but I’m glad I did. At some point, pretty far into the process, I realized that the management was me. And the workers were going on strike because I wasn’t taking care of myself properly. This version of the biomechanics is very different from Solnit’s romantic understanding of walking. I think I went in the direction that I did because I associate learning/being curious about the technical aspects of walking with injury. Why else would I want to dissect the process and learn the specific names of muscles, bones and joints?