Our last and final component of Good Form Running is Lean.  Lean refers to the angle of your body in relationship to the ground.  You should not run bent over, or perpendicular to a flat surface.  Instead, you should lean gently from the ankle, without bending at the waist.  To practice this, while standing still, lean from the ankle, and when you feel yourself begin to fall, step forward to catch yourself.  This posture will use gravity to generate forward momentum.  Your weight should be slightly forward, and your ankles slightly flexed.  After working on this slight lean, reset your posture and take off, leaning in to your run.  All of these components, posture, mid-foot heel strike, 180 cadence and lean will work together to make you fast and injury free.  If you have a bad posture, are striking with your heel and bending from your waist, you will be wasting energy and may have to deal with injuries.  Practice these techniques as you run.  Some days you may wish to focus on just one component, and other days you may decide to work on all of them in combination.  Happy running!