The foot is a marvel of design. Each foot has 26 bones, 100’s of ligaments, muscles and tendons. Many of these components need to function alongside one another in a really precise way in order that we can easily walk, run and perform a whole range of actions. The foot is a perfectly tuned biomechanical work of art as it needs to co-ordinate all those functional structures so that it can function efficiently and effortlessly to carry out those activities. The foot did evolve to acquire those characteristics on a soft surface and never wearing shoes, so a number of defects potentially crept in as feet was placed into shoes and it was forced to walk and run on the hard concrete surfaces. Small faults which were not previously a problem began to show up in those shoes and on those hard surfaces. It is this that is responsible for so many of the problems that podiatrists see in the foot these days.
For example, one of those issues is a theory referred to as supination resistance. This is thought of as the force that's required to lift the arch of the foot. In the event that force is high, then the muscles and tendons need to work harder and the ligaments have a lot more stress on them. This might lead to pain in those structures and also the development of a progressive flat foot. If that force is higher, walking and running also requires more energy and can be very tireing. If that supination resistance force is too low, then it will be easy to raise the arch of the foot. This may result in more ankle sprains as it is very easy to tip the foot over to cause that. From this it should be clear that a fine balance is required between excessive and too low amounts of this force which is a good demonstration of precisely what an engineering masterpiece the foot is and just how simple it is for something to go bad.