Running mechanics have been a hot topic of discussion since before Bill Bowerman took out a waffle iron to create his first running shoe. From the barefoot crazy to custom-made orthotics, it is possible to find someone who swears by their style of running. Many running stores have treadmills with recording equipment set up to help find “the right shoe for your mechanics.”
So what is different when you have your gait analyzed by a physical therapist?
A comprehensive analysis performed by a physical therapist looks at the foot mechanics in several ways—a non-weight bearing state, standing, walking, running at pace (i.e. endurance vs. sprint) and after fatigue. It is also considers more than the foot, a physical therapist will look at the knee, pelvis and low back. Arm swing may also be analyzed to tease out upper body compensations for lower body weaknesses. Let’s look at a few of these in a little more depth.
Biomechanics in a non-weight bearing foot boils down to the functionality of the multiple joints of the foot and how they interact, particularly in a dynamic state. Is your foot rigid, flexible, flat or high-arched? Does your big toe have the motion it needs for push-off? Is the main ankle joint (talocrural joint) moving correctly? What changes when the foot bears weight in standing, walking or running?
At a shoe store, runners are often evaluated while standing, walking, or jogging. Many are told they are pronators. Pronation is a normal part of weight bearing in static and dynamic conditions. In very general terms, as a limb strikes the ground the foot must go through a phase of pronation to absorb and distribute the forces of the body. As we move through a gait cycle, the typical foot will then go through the opposite motion and supinate to act as a spring which helps propel us forward. Pronation is neither an entirely bad thing nor a single action, and pronation during walking may look different when jogging or running or when fatigued.
In part, this is where experimentation with barefoot running or transitioning to minimalist running shoes have gained popularity. Motion control shoes are seeking in part to prevent ‘excessive’ pronation during the gait cycle. Part of the concept of barefoot running centers around what part of the foot strikes the ground first: toe, mid-foot, or heel. The common argument I hear is that if runners move to a mid-foot strike they will be more efficient and can avoid using motion control shoes. I take a slightly different stand.
Rather than forcing a mid-foot strike, runners should focus on increasing cadence (number of foot falls) and speed. As these two things increase naturally, most runners will move into a mid-foot striking pattern. I do agree that if the majority of running is done on the mid-foot, the need for motion control decreases, but is not eliminated, as most of the motion control in a shoe is toward the heel. The second consideration to keep in mind is the assumption that running is only efficient if you strike at your mid-foot, when in reality many factors determine efficiency.
When running, foot strike location in relation to the body position is a major factor in efficiency. If foot contact with the ground is made in front of the line of the body, regardless of where on the foot the contact happens, the foot will act as a break in motion. Ideal foot contact would be under the body to allow forward momentum to continue unimpeded.
What does this mean for the average runner? Think more about where your foot is landing and less about which part of your foot lands first.
Efficiency is also affected by hip strength and mobility, core strength, and arm swing. Runners with a mid-foot strike that translate much of that energy into up and down motion – rather than forward motion — will be less efficient than a heel striker who sends all the energy forward.
All of this is should be considered before we change the shoe platform. The debate over shoe technology has heated up in recent years, and from a physical therapist’s perspective, no one solution exists for every foot type, body type or runner. Changing mechanics and footwear is possible and may be beneficial, however, slow and steady changes are more effective for the long term health of your body.