Running Related Foot Pain & Plantar Fasciitis
John Fiore; Sapphire Physical Therapy
The simplicity of running is one of the main draws to many dedicated runners. All you need is a trail, a road, some free time, and a pair of shoes (or no shoes even) and the world is your backyard. Running becomes much less than a simple activity, however, when foot pain enters the equation. Our feet contact the ground 1,400 to 2,000 times per mile depending on your running or walking speed. The force of each foot contact moment is 1.5 to 3.0 times our body weight depending on your running style and technique. The math produces a staggering number of pounds of force transferred through each foot with every passing mile. An efficient, 150 pound runner transmits 315,000 lbs. of force through their feet per mile. Such numbers cause me pause and thank my feet for all they do day in and day out! It is no wonder, therefore, that foot pain is the most common running related injury I see in physical therapy.
Plantar fasciitis, or pain in the bottom of the foot, is the most common form of running related foot pain. Many factors contribute to the incidence of plantar fasciitis, all of which influence the choice and effectiveness of treatment. While most of us will take time off from running or purchase a new pair of shoes to diminish the symptoms, effective and long-lasting treatment begins with understanding the cause. Running is not reason enough to develop plantar fasciitis. Our feet are designed to run and historically speaking, humans have been running for thousands of years. Our foot is cleverly designed to absorb force associated with initial contact with the ground (pronation) followed by a recoil-type rebound which enables us to push off a stable foot (supination). The muscles, connective tissue, joint, and sensory dynamics associated with the simple act of running must work in cooperative balance to enable us to run mile after pain-free mile.
A thorough evaluation of a runner’s foot structure, gait, running technique, and accessory muscular strength (intrinsic foot, hip, quadriceps, hamstring, gastroc-soleus, tibialis posterior) often reveals asymmetry and/or a deficit on the involved (painful) side. Below are a few key components necessary for running with pain-free feet:
Each foot contains twenty six bones, multiple joint surfaces between each bone, and has a structurally unique fore foot and rear foot. Much like our thumb is the strongest finger in our hand, the great toe (aka big toe or the toe with the black toe nail) is hands down the strongest toe in our foot. In addition to being a weight supporting, impact reducing, propulsive engineering feat, the foot has an amazing sensory system. Running down a rock-strewn trail at a 6:00 minute per mile pace requires split second timing and agility. Our built in proprioception enables us to know where our feet are in space without even looking down. Our tactile sensation confirms proper placement of our foot and allows for accommodations to uneven surfaces. Much like an orchestra with a single out of tune instrument, breakdown or fatigue in one structural component may result in an overuse injury.
Decreasing plantar fasciitis symptoms begins with improving the mobility of the foot. Think of the plantar fascia as the “brakes.” If motion (mobility) within the foot and associated joints is limited, the plantar fascia takes up the slack and applies the brakes to the inertia of the intended motion. Whether your feet have low arches, high arches, no arches, long finer-like toes, or short stubby toes, all foot types can benefit from mobility exercises. Our great toe (big toe) is responsible for 80% of the stability in our foot. The great toe achieves this through flexion (pushing the great toe into the ground as we push off) and extension (lifting the big toe off the ground as we begin to swing our leg through for the next stride). The great toe is the driving force or “brains” of our foot. Without 30° of great toe extension our foot mobility is compromised. Without the isolated ability to push the great toe into the ground the intrinsic stability of the foot during push off is compromised, leading to over-pronation and foot strain associated with plantar fasciitis. A few simple, individualized “foot yoga” exercises will effectively address the foot mobility needs unique to runners with great success.
The plantar fascia similarly acts as the “go-to guy” and attempts to stabilize the foot in the absence of adequate foot strength and/or during the fatigue of a long run or race. Foot stability is achieved though intrinsic foot muscular strength and the delicate balance of pronation and supination which is controlled in the lower leg musculature (fibularis muscle, tibialis posterior muscle). Simply put, pronation allows our foot and ankle to absorb shock and impact associated with running, while supination allows us to push off a stable, strong foot rather than a mushy, collapsed foot. Physical therapists specializing in running injuries can provide you with a balance of exercises to address both of these necessary foot and ankle components.
The Runners Edge staff can describe the pros and cons of the incredible selection of running shoes available. Whether you prefer to stick with the brand and model that work for you, or wish to try a lower profile shoe to feel the ground beneath you, find a shoe that works for you. A bit of cushion protects the foot from rocky trails and compression, but be sure you can feel the ground beneath you. Your running shoes should allow the ground to communicate with your foot and should not interfere with your body’s (hip, leg, lower leg, and intrinsic foot musculature) goal of effectively propelling you forward. A mega cushioned shoe will not take the place of a foot with intrinsic muscular weakness.
Now get out and enjoy some fall running!
John Fiore, PT