Dr. Yessis Sports Training Blog

If you read the many reviews of running shoes and what each shoe supposedly does, it makes you wonder why we don’t have more outstanding runners. But then it may be due to some of the information about shoes presented on a lack of understanding of what occurs in running.

For example, according to an article in Runners World, “…a shoes flexibility is … important in helping the body generate maximum propulsion …” This flexibility is needed since “runners spend 70 to 80% of their time on the balls of their feet as they transition from footstrike to toe-off”.

How is it determined that runners spend this amount of time on the balls of their feet. Isn’t the amount of time spent on the heel about the same –which I presume is what the authors imply. If they land on the ball of the foot or midfoot, then we can agree with this statement.

The need for flexibility is brought out in a statement that “the more flexible a forefoot is, the longer the foot can stay in contact with the ground as the runner strides forward. This is important because the longer contact translates into more traction that the body can use in pushing itself forward”.

But if we use this logic, the longer the foot remains in contact with the ground, the slower the runner will be running. This statement is true only in cases where speed is not important or the body has time to go through a full range of motion for more power.

This can be illustrated when throwing a baseball. The longer the pathway over which you can apply force to the ball, the greater will be the speed at the moment of release. However in running, you want to generate the maximum force possible in the shortest amount of time.

This is why doing plyometrics and other forms of speed-strength training are used to help improve running speed. When you keep the foot in contact with the ground for long periods of time, the slower you will go. This is another reason why the heel hit is inappropriate. It takes too long to transition to the ball of the foot for pushoff.

Thus if you want flexibility in the shoe, which is important and needed, think of it more in terms of proper foot function rather than helping you create greater force. The muscles of the foot and ankle will take care of the pushoff.

For more information on the forces involved on ground contact and in the pushoff, see Explosive Running