One of the distinguishing features of a high-level sprinter is the high knee position on pushoff. To practice getting high knees in running, coaches do drills in which the athlete raises the knees upward in a repetitive fashion. As result, the athlete learns to drive the knees upward during the pushoff.
The high knees in running position is easily seen when viewing a sprinter in person, or when watching his or her video. You can also see many photos in newspapers and magazines showing the runner with a high knee (level or close to level to the ground position). As result the high knee position is deemed a necessary component of the runner’s technique.
However, even though the end result is the same, i.e., the runner has a high knee position, his stride length can be quite different. In effective maximum speed sprinting when the high knee position is achieved, there is great separation between the thighs; up to 160-170°.
In poorer (slower) running, the knee or thigh can also reach the same high point and be almost level to the ground. However, his stride length is considerably less. When the thigh reaches its high point, there is comparatively little separation between the thighs; approximately 110-120°.
Obviously, the greater the separation, the greater the stride length and the faster the runner will be moving. When coupled with a fast turnover (stride frequency) you have a world-class sprinter.
The difference in high knee technique execution is that the runner with maximum stride length drives the knee forward, not upward. In other words, the thigh moves forward with maximum speed, not upward. The key is to begin driving the thigh forward from its most rearward position achieved after pushoff (ankle extension) in the pushoff.
Many runners learn to drive the knee upward because of the drills that they do in practice and if they concentrate on doing this during the run. If they are team athletes and do agility drills such as ladder and rope box drills, they also learn to drive the knee upward rather than forward. This carries over to their running and cutting movements in which you see them driving the knee upward.
To counteract the tendency to drive the knee upward, athletes should do the knee drive exercise with Active Cords. In this exercise the athlete assumes a standing position with the thigh back as far as possible. From this position, with the hip flexor muscles on stretch, the athlete drives the knee forward against the resistance of the cord. Because of the forward drive the runner rarely approaches the thigh level position.the only exception is when the athlete does the exercise in an explosive manner.
The knee drive exercise with Active Cords is perhaps the most important strength exercise that runners or athletes who run in their sport, can do. Not only does it significantly improve speed, but when done for a higher number of repetitions makes it possible for the runner to maintain optimal stride length for the entire distance.
In doing this exercise the athlete develops an effective neuromuscular pathway to not only correct his technique, but also to enhance it. For more information on execution of this exercise see Explosive Running and Biomechanics and Kinesiology of Exercise