The foot has 26 bones and 33 joints. There are over 100 muscles, ligaments and tendons from the knee down. These are all responsible for the movements of the foot while walking.
When you walk, each foot repeats the same movements over and over. These movements come together to create the gait cycle.
A gait cycle consists of the heel strike, the mid stance and the propulsion phase (the pushing off of the toes).
During mid stance, one foot is on the ground and the opposite foot is in swing phase. The foot on the ground is bearing all of the body’s weight while the other foot swings through to begin the cycle all over again.
During swing phase, the foot on the ground is bearing 1-1/2 times the body’s weight.
While jogging, the bearing weight is 3 to 5 times the body’s weight.
During running and impact sports, the weight-bearing number rises to as much as 8 to 12 times the body’s weight.
With each weight-bearing increase, the risk of injury also increases.