The running world has been inundated with buzzwords. Run form, overpronation, minimalist running, and hip strength are only a page turn away in your favorite publication. While these terms are important, their regurgitation often overshadow other relevant topics. Without even understanding the intricacies of the term of overpronation, you’ve likely been exposed to the term, whether you first laid eyes on it in a magazine, online, or simply heard it being tossed around in your local shoe shop.
But what about underpronation? Underpronation affects a large percentage of the population. Anatomically speaking, it presents a set of challenges to runners who fall in this forgotten group. It was once thought that a flat, lower arch was a detriment to runners. Flat arches became synonymous to overpronation while those with high, rigid arches went completely unnoticed (Having low arches DOES NOT mean you overpronate).
As we outlined previously, the natural motion of our foot while running is to land towards the outside of the foot, setting the foot to spin inwards and absorb landing forces. The motion is a combined motion from the entire foot, including the fore, mid, and rear foot. Without pronation we lose shock absorption, which may influence loading rates and the types of injuries that occur. A recent 2014 study in the Journal of Athletic Training found that runners with higher, rigid arches exhibited a higher initial loading rate and greater peak vertical ground reaction force (impact) when compared to runners with a mobile high arch.1 Anatomically this makes sense. Without a flexible high arch your foot can’t spin. If your foot can’t spin its ability to absorb shock is nullified.
Your landing forces are ultimately the same. We’re not changing gravity nor your body weight. What changes is your means to control the collision between your body and the ground. Simplified, your body’s three tier shock absorbing system (ankle, knee, and hip) has been reduced to two (knee and hip).
Why won’t my foot spin?
Sometimes you’re dealt a tough hand. Some individuals are structurally rigid based on development or genetics, while others acquire a rigid arch through a traumatic injury (ie fracture). A high rigid arch will not often convert to a flexible one, although you may be able to squeeze out a few helpful degrees. Luckily, our body has an amazing ability to accommodate a rigid arch. Your knee, hip, pelvis, and spine can find you your range of motion to keep you on the road, but keep in mind your foot might be an injury risk for you moving forward.
Prior Injury / Surgery
Prior injury and surgery is often overlooked during treatment as a causative factor for lack of foot spin. It’s not uncommon to find a runner who will avoid spinning their foot inwards. It often occurs unbeknownst to the runner. It can occur for a variety of reasons. Two common occurrences are to avoid a painful heel (plantar fasciitis) or prior surgery (bunionectomy). Kernozek and Sterikker2 found decreased plantar pressure while walking one year post bunionectomy. A bunionectomy, a procedure that reconstructs and realigns the first toe, caused patients to walk on the outside edge of their foot. Clinically, this happens more often that you would think (research finds improved function and ambulation through physical therapy and gait training). Through subconsciously altering movement the body will avoid spinning inwards at all costs. For some it’s to avoid a painful inner heel, while others avoid a reconstructed big toe. This is true for those with a neutral and low arch as well. Through this alteration a runner may actually function as a high, rigid arch but display a low, flexible arch upon exam.
Just like a muscle can become tight, so too can your foot. The majority of our “spin” comes from our midfoot. Tightness can occur for various reasons, including prolonged motion control shoe use. Blocking your foot from pronating can eventually cause adaptive tightness, limiting your inward spin. Luckily, improving your spin can be improved with selective exercises that promote pronation. Try this exercise.
The first step is always identifying the cause of your underpronation (or lack of spin). The above examples are overly simplified and are the tip of the iceberg. Finding a skilled clinician can make all the difference when determining your course of action. For some, pronation or “spin” can improve, while others are simple rigid with little to gain. Go find a skilled physical therapist who can help you.
1. Williams, D.S. Blaise, III, Robin N. Tierney, and Robert J. Butler. “Increased medial longitudinal arch mobility, lower extremity kinematics, and ground reaction forces in high-arched runners.” Journal of Athletic Training 49.3 (2014): 290+. Academic OneFile. Web. 16 Dec. 2014.
2. Kernozek TW1, Sterriker SA. Chevron (Austin) distal metatarsal osteotomy for hallux valgus: comparison of pre- and post-surgical characteristics. Foot Ankle Int. 2002 Jun;23(6):503-8.