Three robots in different colours

Walk like a man

What steps are involved in walking?

Walking may seem as simple as putting one foot in front of the other. Analyse the motion, though, and at any one time you are balanced on one leg as you move forward. That leg pivots around the planted foot and transmits force from the ground up to your hipbones, initially slowing you down.

As you slow, you also push upwards, then you start to accelerate again. You might simply fall forwards, but you swing the other foot in front of you just in time to begin the next step. The degree to which bouncing, by flexing tendons in the leg and foot, is involved in walking (as it definitely is in running) is still being studied by biomechanics experts.

Watch a toddler taking their first steps, or someone recovering from a stroke learning how to walk again, and it’s clear that the coordination needed is tricky to master. Constant small adjustments are needed to keep a person upright and moving forward. The patellar, or knee-jerk, reflex is routed through the spinal nerves for speed so that it can contract the thigh muscles almost instantly when the foot is loaded.

Without that contraction, you would stumble at every step. Walking also needs good proprioception, or a sense of exactly where your body is in relation to your surroundings. Losing this sense is why you lose your footing if there is one more – or one less – step in a flight of stairs than you thought.

Robots that mimic human walking are now available; take a look at some examples here in this article, and in this video.

Lead image:

Rog01/Flickr CC BY

References

About this resource

This resource was first published in ‘Exercise, Energy and Movement’ in January 2012 and reviewed and updated in August 2016.

Topics:
Physiology, Biotechnology and engineering
Issue:
Exercise, Energy and Movement
Education levels:
14–16, 16–19, Continuing professional development