Taken from the book Tread Lightly by Pete Larson and Bill Katovsky.
http://www.treadlightlybook.com/

Dr. Mark Cucuzzella is a family physician and the owner of the nation’s first minimalist shoe store, Two Rivers Treads, in Shepherdstown, West Virginia, which opened in the spring of 2010. A top masters runner, who at the age of forty-four won the 2011 Air Force Marathon outright, Mark is also the ex-ecutive director and co-founder of the Natural Running Center. He shares his experience, insight, and wisdom about pronation, proper fit, and how to find a “running shoe” that best works for you.

When customers enter our store, questions always arise about pronation. Many of them have been labeled in the past as pronators by well-meaning employees at other running stores. Some claim that they have been classified as supinators. All they really want is shoes that fit, and that will help them to run injury-free. Yet the process of determining which shoe will best meet their needs is not something so simple as watching them walk or jog ten steps across the store floor. This kind of evaluation certainly won’t help the runner find the right shoe. So the first thing we do with these customers is have a conversation. We explain what pronation is. Then, we discuss the shoe-fitting process. We don’t rush through this either. Every runner is unique. Some will need shoes with greater or lesser support and mobility control, depending on his or her foot strength. Pronation is a normal function in the gait cycle, just like bending the knee or extending the hip. Pronation control can be achieved with your foot (ideal-ly), with a shoe/insert (maybe), or both. Maximum pronation actually occurs when your heel is off the ground, so the foot’s role in this process is critical. Let’s start with the foot itself, a remarkable engineering feat as de-scribed by Leonardo DaVinci: twenty-eight bones, multiple arches, and accompanying muscles and ligaments that move dynamically to balance, stabilize, and propel one forward. Children running barefoot naturally feel the ground and their muscles work reflexively to provide pronation con-trol. Runners (with or without shoes) who have strong feet have the abil-ity to control this motion just fine. The foot works best when it receives sensory information on where it’s landing, and a firm surface is best for feedback. Overly soft shoes delay the feedback. Remember that a runner’s foot is on the ground for only a few fractions of a second, so the pronation control must be immediate and strong.

Spending a lifetime in stiff, overly cushioned, and supportive shoes has diminished natural pronation control for most modern-day runners. The shoe has done some or all of the work for them. To see for yourself, try bal-ancing on the ball of one foot. Can you hold the position for a second? Ten seconds? Thirty seconds? Can you pop off the ground with springy recoil while jumping rope? If you are having difficulty, then you may need to take certain measures if you want to transition to more natural pronation control and run in a true minimalist shoe. Why is natural pronation control better? The foot is the magic spring that adds elastic recoil to our stride. This is free energy. When the foot is constricted by being made to “move” within a rigid shoe, it cannot work well as a spring and you need to apply more muscle force to the stride. More muscle use results in greater fatigue and less efficient running. My recommendation to all runners is to make a gradual transition if you want to strengthen your feet. Do plenty of walking barefoot and in minimalist shoes. Start your transition to running slowly and remember that your muscles, tendons, ligaments, and bones are adapting and do not have the capacity for the added load yet. Do supplemental foot strengthen-ing throughout the day. Stand on one foot, balance on the ball, walk bare-foot in the house and outdoors when you can. This can only help your run-ning. You may have a little soreness like with any new training. Tissues are lengthening and strengthening. Extreme soreness means you are progressing too quickly and asking the tissues to do too much too soon.

Proper Fit Explained
Two years before I opened Two Rivers Treads, I had completely rethought how a shoe should fit. It involves much more than just picking a size and sticking with it. Sizes and fit vary from shoe to shoe, and our feet can change size and shape over time. For example, I have started running many more true barefoot miles over the last year and my foot has greatly increased in thickness—I now need to consider this change when choosing a shoe. At our store, we defy old-school thinking about sizing and narrow-shaped, ill-fitting conventional shoes. Improper shoe sizing and shape are the primary cause of ingrown toenails, bunions, corns, hammer toes, and hallux valgus. Shoes that don’t fit your feet correctly can also lead to muscu-lar imbalances in the body, leading to foot, knee, and hip injuries. A proper fit accommodates the natural expansion of the foot upon ground contact. Excess waste is eliminated, along with everything that inhibits your foot’s natural motion. Your foot is free to move and work the way nature intended it to; the way of its own barefoot motion. Call it toe-wiggle freedom. We educate on how to safely and gradually make this transition. Yet, with sizing, most get it wrong. First, abandon the notion that you have a shoe size. Instead you have a foot size. Shoes are made all over the world and apply different shapes and standards. If you measure your foot while seated with a traditional measuring tool like a Brannock device and base your size on that you will likely be off by one to two sizes in a running or hiking shoe. Increasing one full shoe size is equivalent to adding only 1⁄3

an inch to the length of the shoe. Also critically important is that the Bran-nock device measures the widest part of the shoe at the ball. Infants and habitually barefoot individuals have feet that are widest at the ends of the toes, not the ball of the foot—this is the natural alignment of the human foot, and shoes should respect this. Here’s why many people are wearing shoes that are too small: • When a load is applied to a foot by running or with a pack weight your foot will spread in length by up to half an inch.
• You need at least 1⁄8 inch or more of space in the heel and toe to allow space for a sock.
• You want 1⁄3 to 1⁄2 an inch of space in front of your big toe to allow room for loading and splay.
• Your foot will increase in width by 15 percent due to splay under load.
• Your foot is widest at the toes, and unfortunately most shoes are not shaped this way.

tips on sizing:
• Do not assume that you are the same size in every shoe.
• Take your time and try several shoes on. Go run in them. Do not try them on while sitting.
• Always try both shoes on. If your feet are slightly different in size then fit the larger foot.
• Take the removable insole out of the shoe and see how your foot fits against the insole as a template. Is there room at the toes or does you foot spill over the insole? If there is no room to spare or if your foot spills over this shoe will not fit comfortably.
• Keep going one half-size up until the shoes are obviously too big.
• Try on shoes at the end of the day when feet are most flattened and swollen.
• Try shoes on with the type of sock you will wear for activity.
• For women, you may fit better in a men’s shoe for width.
• Do not lace the shoes up tight. Allow spread in the midfoot and forefoot.
• Go up onto the ball of the foot. Can you put your index finger between your heel and the back of the shoe? If not, the shoe is likely too small.
• Consider not using the soft insole. This takes up space in the shoe and can interfere with ground feel.
• Walk on a firm surface when trying shoes on, not a carpeted one.
• If you are a runner you must run in the shoe. What feels nice and soft when walking is the opposite of what you need when running. Look for firmer base to allow for better sensory input and to facilitate stabilization.

Children’s Shoes:
What children wear growing up has a strong influence on foot structure and function when they are adults. Given this, selection of healthy footwear for children is critical. You should select proper shoes for your children based on the following:
• Ultra-thin soles to allow adequate sensory perception, proper neuromus-cular activation in the entire kinetic chain, and to complement the body’s natural ability to absorb ground reaction forces. • Low, flat to the ground profile—shoes should not have a slope from heel to forefoot.
• The materials should be soft and supple, thereby allowing natural foot function. The shoe should bend easily at the toe joints—this is where a foot is designed to bend to lock the arch on takeoff.
• The toebox should be wide enough to allow natural toe spread. Foot sup-port is created by the natural arch of the foot with the great toe helping to stabilize the arch. When the great toe is pushed in toward the second toe (a common design flaw in many shoes which come to a tapered point), this stability is compromised. The foot produces the most leverage when the toes are straight and aligned with the metatarsals. A child’s foot is widest at the ends of the toes (as should an adult’s be if they have been in proper shoes or barefoot).
• A single piece midsole/outsole allowing protection on unnatural surfaces (concrete, asphalt) and natural rough surfaces (rock, trail) while allowing sensory perception and natural dissipation of ground reaction forces.
• Upper material should be soft, breathable, and washable.
• Discourage the use of thick, heavy socks as these can constrict the foot and interfere with sensory perception.