The biophysics of walking

Geetha Iyer

Walking is something most of us take for granted. Modern day lifestyle having turned sedentary, it is now the prime form of exercise. Walking naturally brings to focus the limbs and by extension a memory of lessons of the skeletal and muscular system.

To understand walking one needs to know beyond the skeletal parts or muscles. There are principles of physics that can help us understand the stance and the movements we take when we walk. In fact if you want to be part of the footwear industry, to create different types of footwear you will need to have knowledge of principles one learns under both physics and biology.

For the middle school classroom, walking is a very good activity to learn about the musculoskeletal system and the principles of force and pressure. It is not just walking, but any lesson that involves locomotion of animals or humans should be learnt in an integrated manner. Physics teachers can provide concrete experiences for abstract concepts relating to force, pressure, etc., if they use examples from the living world. Life and the chemical molecules that construct living organisms follow the same laws that physics tries to explain in the realm of non-living. Walking is one example.

To understand the mechanics of walking, it is important to understand the foot anatomy. The human foot is made of 26 bones, 33 joints and more than hundred muscles and tendons.

There are three parts to a foot – hind-foot, mid-foot and fore-foot.

foot-diagram The hind-foot: The ankle and the heel, which are important bones involved in movement, form the hind foot. The tibia or the longer bone of the leg forms a movable ankle joint with the tarsal bones of the foot. The heel bone is the largest tarsal bone and rests on the ground when the body is standing.

The mid-foot: The arches of the foot are formed by the tarsal bones and act as shock absorbers. The body weight is distributed among the seven tarsals, which can move slightly to provide minute adjustments to the position of the ankle and the foot.

The author is a consultant for science and environment education. She can be reached at

This is an article for subscribers only. You may request the complete article by writing to us at