Striding Right (updated)
Author’s Note: This article, which originally appeared some years ago, has been updated to address related injuries I have seen recently.
Every so often a runner will ask me, “should I change my stride?” Now, this may be asked in reference to treating or preventing an injury, or it may be from a suspicion that altering one’s gait pattern will result in faster running or greater endurance (or both!).
I can certainly understand where this comes from; years ago I would watch Steve Prefontaine or Jim Ryun racing on T.V. and marvel at their fluid, graceful strides that seemed to gobble yards and yards each step, and with such little apparent effort! If I can look like that, I thought, I can run as fast as they do. And so I would go out with a firm mental picture of the perfect running form, try to imitate it as best I could and…well, obviously you know it didn’t work since none of you ever saw me in the Olympics. Not only did I not run any faster, but I discovered very quickly that I could not maintain that “perfect” form for very long without becoming very fatigued. I was disappointed, but at least I could take consolation in what I thought was the perfect excuse: my legs are so much shorter than those guys’, even if I “look” like they do when I run I couldn’t possibly match the length of their stride, so of course I run slower! Then along comes little Joanie Benoit and out goes that theory.
I suspect many of you have gone through this little scenario yourselves at one time or another and, like me, have found through experience that trying to change your running stride doesn’t really work. Perhaps it will give you some comfort to know that this has been scientifically validated as well. Dr. Peter Cavanaugh, world-renowned Professor of Biomechanics as Penn State, and others have researched the relationship between leg length, stride length, running speed and efficiency. Some of the findings:
- at any given speed of running, each individual has a stride length that is “optimal” in terms of minimizing the energy needed for running;
- forcing an individual to lengthen or shorten his/her stride even slightly will result in an increased energy cost of at least 1-2%;
- contrary to common assumption, tall subjects do not always have longer optimal strides than shorter individuals.
Based on these findings, it seems obvious that we are not likely to enhance running performance by consciously lengthening our stride. But perhaps more important is the need to recognize the potential for injury that arises when we try to overstride. Generally, runners who try to increase their stride length do so by “reaching forward” with the foot as it is about to land, rather than by pushing off more forcefully. Such misguided action creates two potential problems:
- The hamstrings are overstretched during the final phase of the swing phase of the leg. This excessive eccentric (lengthening) motion causes greater strain on the muscle fibers, leading, over time, to eventual failure. It is not uncommon to see chronic hamstring problems be traced back to the runner’s attempt to increase speed, especially during speedwork or track sessions, in this manner.
- Ground reaction forces are increased at the moment of heel strike. Most people believe that since their heel makes contact with the ground first, it must be out in front of the body. Slow-motion viewing of running movement, however, clearly shows that while it may be true that the heel touches first, the foot and entire lower limb are actually already moving back at the moment of contact. This movement looks much like an animal “pawing” at the ground. Throwing the leg too far forward and eliminating this pattern results in a “braking” action that severely increases the shock of body weight/ground reaction forces imparted all the way up through the lower extremity. This increases the likelihood of injuries throughout the limb and low back.
It comes down to this: your body knows what’s best, not only in terms of overtraining and injury as we have seen before, but also with respect to what is most efficient. Listen to it and let it run the way it wants to.