The choice of which running shoe a runner should use is largely determined by their foot arch and the type of motion the foot makes through the stance phase (the portion of the running cycle when the foot is in contact with the ground).
There are two common subsets of foot and motion patterns seen in runners. The most common pattern is the overpronator, which is often associated with a flat arch. The second and less common category is the high-arched underpronator, which happens to be the category I belong to.
To understand how these foot mechanics influence choice of footwear, it is important to understand foot pronation. Foot pronation is a natural roll of the foot that occurs during stance phase that serves to help absorb some of the force of impact. When the foot first contact the ground, most people start to roll almost immediately to the outside of their foot (this is why, if you look at the shoes of most people, you see greater wear on the outside of their heel than the inside of the heel). What happens in the middle of stance phase is that weight stays along the outside of the foot arch as the runners body weight is transferred over the middle of the foot.
The main distinction between over- and under- pronators occurs during the end of stance phase. Underpronators start rolling toward the big toe, and keep on going. This pronation is useful, as it helps absorb the force of landing, which is several times bodyweight. The problem with overpronating is that as the foot keeps rolling without control, it drags the rest of the body with it, which causes excessive strain up the kinetic chain (e.g., the excessive pronation can pull the leg bone, the tibia, with it the foot, which can cause strain at the knee). Therefore, runners with excessive pronation are often advised to wear motion control shoes.
The underpronator, like me, has the opposite problem. In their feet, the foot does NOT roll sufficiently toward the big toe. Remember- pronation is an important shock absorbing motion. Therefore, in runners with high arches and underpronation, the general recommendation is to avoid motion control shoes and use running shoes that have extra cushioning (to compensate for the lack of absorbtion from the natural pronation motion).
A recent study from the American Journal of Sports Medicine confirmed the shoe recommendations for high-arched runners.
Caleb Wegener, Joshua Burns, and Stefania Penkala Effect of Neutral-Cushioned Running Shoes on Plantar Pressure Loading and Comfort in Athletes With Cavus Feet: A Crossover Randomized Controlled Trial , Am J Sports Med 2008 36: 2139-2146
In short, this study confirms the recommendations above for the high-arched runner.
For the record, the cushioned shoes that were examined were the Asics Nimbus 6 and Brooks Glycerin 3, and the control shoe that was examined was the Dunlop Volley. This was a well designed study that used a cross-over study design, meaning that each participant started with either a cushioned shoe or the control, and then switched groups. The examiners also assessed both pressure distribution and comfort level of the runners.
Based on this study, the recommendations listed above still apply. Based on my personal anecdotal experience, it is important for runners with high arches and underpronation to look for a shoe that is BOTH heavily cushioned AND not motion control. My experience has been that it is hard to find running shoes that do not have some component of motion control built into the shoe. Since overpronation is the more common foot problem, most shoe manufacturers tend to build some motion control into almost all of their shoes, even their heavily cushioned models.
As a practical matter, this can be a challenge. If you go to many running shoe stores, the clerks sometimes will not know the properties of the individual shoes. My recommendation is to first scout out the shoes you are looking for on a good running shoe site (I tend to use RoadRunnerSports.com), and then look for shoes that fit your category. Once you find a shoe you like, stick with it. Stores that specialize in running shoes (e.g., in Chicago and Pittsburgh, Fleet Feet is a good store) tend to have experienced sales people with good knowledge of what type of shoe is right for you.
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