Basically, the subject of running injuries comes down to static versus dynamic runners. Static runners get hurt, dynamic runners do not. Have you ever watched a world class track meet and said to yourself “boy she runs so smooth, that’s what a runner looks like.” Running injuries are simple to assess but difficult to treat because how do I make a “regular” runner look like a world class runner? The truth is, you cannot make a mule into a miler. But what you can do is teach the principles of efficient running. Lets begin with a vocabulary lesson.
Ground Reaction Force: the reaction to the force the body exerts on the ground. In other words, this is the pounding a body takes while running. Running ground reaction force has been shown to measure about 3-5 times the persons body weight during easy to moderate running and as much as 7-9 times with sprinting.
Vertical Displacement: the shifting of the center of mass in a vertical direction, resulting in a change in elevation. Or, how much your body bounces during running.
Running Efficiency or Running economy: the measure of how efficiently a person uses oxygen while running at a given pace. Or, the ease in which a person runs.
To sum up these terms, the more economical a person runs the more he/she controls the amount of ground reaction force by minimizing vertical displacement. The more fluid the force moves through the body the more dynamic the runner runs. If a person is bouncing too much–maximizing ground reaction force–the less economy, and the more pain a person will experience.
Now lets get back to injuries. Running injuries can be treated palliatively with fancy equipment like foam rollers or “sticks” ( a popular massage device). Rubbing/massaging makes for short-lived relief but at the end of the day the running gait must become more economical. The force must be minimized. Here are principles of efficient running:
Proper Foot strike: Studies cannot say that forefoot or midfoot is the best way to go. The reason is that whether your forefoot or midfoot hit first only matters where the foot hits in relationship to your center of gravity, which is where the ground reaction settles. If you reach out the leg to strike with the heel, your leg is working way to hard. Moving the foot strike to underneath the center of gravity makes for less vertical displacement and more efficiency.
Proper Strength: If it comes down to force transmission and you are unable to decrease the ground reaction force, the body must increase the strength to dissipate ground reaction force. The muscles most commonly requiring more attention are glutes, quads, calves, and toe flexors/extensors. The glutes control the hip and knee position while the quads support the shock absorbing knee. Calves/toe muscles work to use the foot as a force “dampener.” When they all work together they function like a symphony to run more economically.
Proper Pacing: What if you are going too slow? What if you are going too fast? There are plenty of tools available online to assess your proper pacing by using various race results. Here are a few, mcmillan or Vdot.
Proper footwear: Not too much shoe or not enough shoe. See “You mean I cannot wear the cute ones?”
When you report to physical therapy, make sure you do your homework. Not every PT knows about running. We get very minimal run training in school. Ask around. Find out who is performing one on one care and knows about running. Interview the PT. Ask them how many running-specific continuing education courses they have attended. As you can see there are many factors influencing healthy running. If you run dynamically you are running economically. Finding a balance between lowering ground reaction force and increasing muscle strength is the difference between running pain-free and economically and running poorly with pain.