Phase 1: Stance Phase
Let’s begin with the “stance phase.” The stance phase refers to the portion of the gait cycle when your body makes physical contact with the ground. To keep things simple, we can divide the stance phase into three distinct subsets: initial contact, mid stance and propulsion.
As the name implies, this is when your foot starts to hit the ground. This can be visualized as the part of the gait cycle where you are cushioning your body, and absorbing the vibrations generated from the ground reaction forces created by your foot strike. For every action there is an equal and opposite reaction (Newton’s third law of motion), and in running these vibratory forces can be up to three times your bodyweight in magnitude. As you hit the ground, your subtalar joint (a joint between two tarsals on your foot) pronates slightly, your knee bends at an angle and your entire leg rotates internally to help absorb the impact and prepare for the next phase.
Coach’s Note: The debate over “heel striking” in pop culture has started to cool off recently, once we realized what scientists knew all along: the part of your foot that makes initial contact with the ground is less important as where that point of contact is in relation to your center of mass. Heel striking is just a symptom of an “over stride,” which places the point of initial contact TOO far in front of the rest of your body. This is why good coaches will always cue you to “lean from the ankles.”