What came first: stride length or running speed?
The fastest runners have a long stride length. This may encourage some people to focus on increasing stride length in order to increase running speed. They should be careful to consider whether stride length is a cause of speed, correlated to speed, or the result of speed. If stride length were the cause of speed, then reaching ahead and taking big steps would result in a faster running speed. Since this doesn’t happen, stride length is, at most, correlated to speed. What if stride length is the result of speed? If this is the case, then the many other components of running should be emphasized rather than stride length. If stride length is a result of speed, it could be used to measure progress, but shouldn’t be a developmental focus - it will increase as the other components are strengthened, coordinated, and connected.
If the foot contacts the ground under the hips, then reaching ahead of the body with the foot will not be an option for increasing stride length. Since the foot should always be contacting the ground under the hips, stride length is determined in part by how far the body moves forward after the trail leg leaves the ground. How far the body moves in the air is determined by the speed of the body. Another main component determining stride length is how far behind the hips the foot leaves the ground. This distance depends on the length of the leg and the angle the thigh rotates past vertical. Focusing on increasing this angle seems like it could throw off the stride frequency. Rather than focusing on this, a more productive focus might be to apply maximum horizontal force pulling the foot backward. This will propel the body further through the air producing a longer stride length. This combined with the other components of good running mechanics help the body move further forward also resulting in a longer stride length.