September 01, 2006
We have outlined a model of acceleration mechanics that emphasizes the importance of training the body to handle explosive single-support applications of force (as described in issue 44 of the CrossFit Journal). Moving the body from zero to 20 mph (11.25 seconds per 100 meters) is a seemingly simple yet highly complex task for the athlete to perform. It requires specific strength applied in a purposeful, concerted manner.
When performed properly, it can be a real thing of beauty. When the athlete is untrained or improperly taught, however, it can be devastating to the body. Fortunately, high-velocity running is a skill that can be improved in every athlete, by improving either stride length or stride frequency, or both.
Biomechanics teaches us that human movement can be traced along three planes: the sagittal/ longitudinal (splitting the body from side to side); the frontal/lateral (splitting the body from front to back); and the transverse (splitting the body horizontally, as to account for rotation.) Most people think of high-velocity running as occurring in just one plane--only as moving the body forward in the shortest amount of time. But running is much more than that. We cycle the arms and legs through the front and back, we move our bodies from right and left, and we fight rotation in our trunk.