The human foot is supremely efficient at carrying the body in a variety of gaits and strides. It also plays a major role in facilitating climbing, crawling, swimming, kicking, jumping, height extension and aiding balance.
The human foot essentially adapts to whatever demands we place on it. In martial arts, feet are used in ways, from kicking to strangling. Our feet have a lot of demands placed on them, but we can learn to support their anatomy for injury prevention.
Consider the foot as a combination of several dimensional variables of strength, durability, sensitivity, and finesse. All of these variables can be improved over time and adaptation. There are 26 bones connected through 33 joints in the human foot. These bones are very stout with lots of surface and knobby ends. They connect more than 100 muscles and tendons.
The foot moves through tendons leading to muscles in the lower leg. Foot muscles work to absorb impact. Tendons are slower to regenerate than muscle, and they strengthen in response to stress. Because the foot has such a large proportion of bone and tendon relative to other body parts, it generally takes longer for it to become conditioned to new stress.
Feet are so durable that they will tolerate abuse through poor form longer than other body parts. This can lead to a false sense of progress in an athletic endeavor until poor form finally causes the foot to injure. Injuries throughout the leg and body may also be caused by poor foot form.
Feet are amazing and they will do whatever you want them to. Special attention to good form is essential for injury prevention. Whatever your sport is, examine your feet and help them adapt slowly over time.