The Right Fit: Shoes
Posted: January 26, 2009
By Steve Sisson
Two major concerns for any runner, regardless of their experience or fitness level, are comfort & remaining injury free. You will begin to realize, if you do not already, how important the shoes you train in are to your continued progress. As you embark on marathon training, you will ask your body to handle new stresses, & it will be very important to minimize discomfort in order to remain motivated for the duration of the program.
The principle reason for quitting a training program is injury. Doing too much too soon causes a majority of injuries, but approximately 30% occur because of inappropriate or worn out shoes. It makes perfect sense, if you think about it: the barrier between your feet & the surface you are traveling across cushions the pounding of hundreds of pounds per square inch. Multiply these thousands of pounds by the average number of times the foot strikes the ground per mile (depending upon stride length & pace, approximately 6,400 times) by the number of miles you are running, & you begin to see the weight your feet are forced to bear. Of course, humans have been running for as long as they have been in existence, & the foot is extremely well designed for this purpose. However, over the last few hundred years (a blip on the evolutionary screen), we have protected our feet with shoes to the point that they are less adept at handling the forces that bear upon them, & we are becoming dependent (whether physiologically or psychologically, I can't say) upon shoes to shield us from the earth. It is not just the earth we are frequently traipsing across. Man has created new synthetic surfaces, such as asphalt & concrete, which are significantly firmer & better suited to motorized vehicles than to the foot. These surfaces do not have any cushioning properties & can cause serious foot injuries without proper foot equipment.
Cushioning is not the only crucial element in shoe selection. The type of shoe that you run in needs to fit your biomechanical needs. Anyone who has stood before a shoe wall at a running specialty store recognizes the sheer number of choices presented to the runner in this technological age. This choice can be daunting if you do not have an experienced, informed shoe technician to guide you through your selection process. A shoe tech looks to see how your foot moves & how this movement affects the rest of your legs, from your ankle through your hips.
When you go to purchase a pair of shoes you should always try to bring your current pair of shoes. If you are not running, bring a pair of shoes that you use for athletics or walking. These shoes will speak volumes to a quality shoe technician. They are looking at wear patterns that you exhibit: which areas of the outsole show the most wear, whether the heel or the fore foot strikes first, how the mid-sole compresses, whether you indicate a tendency to pronate or supinate, if there is anything unusual about the wear of the upper that will indicate bunions or an extremely wide or narrow foot and so on. Before the shoe tech even sees your feet (provided you brought your current shoes), he or she should be able to determine your general biomechanical propensities.
When they look at your feet, the shoe tech is principally determining the flexibility & length of your arch. The flexibility of the arch will indicate a runner’s biomechanical tendency: a highly flexible arch usually will indicate a heavy pronator, this is because the arch does not fall directly down, it collapses in, or medially; a rigid arch will indicate an even foot striker or a supinator. The level of flexibility will
determine the amount & type of support you need in your shoe. The shoe tech should also look at the length of your arch to see what brands of shoes will work best with your arch type. The width of your foot, narrowness of your heel, length of your second toe & any other unusual attributes of your foot will also be taken into consideration when the shoe tech determines which shoes will mostly likely work for you. The shoe tech should also ask to see you walk barefoot, in order to see if you splay your feet out as you walk, or if you walk pigeon-toed. Any amount of toe in or out will have an impact on your knees & needs to be take into consideration when selecting a shoe.
You should expect to move up a half or full size from your dress shoe when purchasing running shoes. There are two reasons for this. First, the sizing standard is flexible in the running shoe industry, each factory has subtle variations &, as the uppers are glued to the mid-sole, the sizing is affected. Secondly, your foot will swell inside the shoe as you run &, if you purchase a shoe that is too small, it will cause blisters or black toe.
The life of a shoe is completely dependent upon the compression of the mid-sole. For this reason a shoe may look like it has many more miles left in it when actually it is completely broken down. A runner's weight, the frequency of use, the time of year & other factors will determine how long your shoe will last. Most mid-soles can be expected to last between 350-450 miles. We recommend you write the date you start running in your shoes inside the shoe or in your running log so you will have a better idea of when they will break down & be prepared to replace them. If you do not have any idea of how many miles you have on your shoes, you can usually tell if they are broken down by new aches & pains in your knees, Achilles, lower back or hips. As you become more familiar with your body & its pain thresholds & indicators, you will have a heightened sensitivity to when your shoes are ready to be replaced.
