Choosing the Right Shoe
Regardless of what sport one plays, running is often a pivotal component of the activity. The fact that the feet are subject to a force up to ten times a runner's body weight every time he or she makes contact with the ground highlights the stressful nature of the exercise. A runner's foot is said to strike the ground up to 600 times a kilometer. Given the repetitiveness of the activity and the amount of impact it imparts to the body, it is not surprising that running is the leading cause of injury in sport. Even though training errors are the major source of running related ills, improper equipment can also lead to problems. With the availability of so many different shoes on the market, choosing the right one can be a daunting task. However, with some basic understanding of foot mechanics and shoe components, making the right choice becomes easy.
The foot is comprised of 28 bones that form 25 joints. It can be split up into three parts: the hindfoot (the heel), the midfoot (the arch) and the forefoot (the toes). During running the foot must be able to provide stability to the athlete but also be flexible enough to absorb shock. This is achieved by complex interactions between the different joints in the foot at different stages in the running motion. One step can be divided into parts: stance phase (when different parts of the foot are on the ground) and swing phase (when the foot is traveling freely through the air). When the heel hits the ground, the foot goes into pronation (flattening of the arch) which helps unlock the foot so that it can absorb shock and adapt to different surfaces. Supination (raising of the arch) locks the foot and enables it to become a rigid support, providing structure during push-off.
The shoe is divided into two parts:
- upper (surrounds the foot)
- lower (supports the foot)
- located at the front of the shoe
- protects the toes and forefoot
- should be made of one piece and wide so that toes aren't compressed
- located at the front of the shoe
- stabilizes the rearfoot and provides cushioning for the heel
- should have a straight seam and be lined with a heel collar to protect the Achilles tendon
- located on the top of the shoe
- accommodates for different foot widths and helps stabilize the foot in the shoe
- if a shoe fits correctly there are about 2-3 cm of space between lacing
- part of the shoe that comes in contact with the ground
- made of durable rubber to provide traction, flexibility and cushioning
- look for studs (circular) if using in dirt or low profile bars for hard surfaces
- between the upper and lower parts of the shoe
- shock absorber for rearfoot
- adds control during pronation phase
- made of EVA (ethylene vinyl acetate) or polyurethane
- EVA - less durable and dense but soft in cold temperatures
- Polyurethane - more durable but provides less shock absorption in cold temperatures than EVA due to its density
When choosing a shoe, determining whether you tend to overpronate, (excessive flattening of the arch when your foot hits midstance) run with a neutral foot or supinate (run with a raised arch on mid-stance) helps narrow down your choices. Pronators need a shoe with increased arch support, a denser, wider midsole and a reinforced heel counter to provide some motion control. Supinators need maximum cushioning so shoes with a lighter midsole, less medial support and a lot of flexibility are appropriate. For neutral runners, mild arch support and a moderate shock absorbing midsole are best. A quick and easy way to test which category you fall into is by doing a squat while maintaining your heels on the ground. If you notice that your arches flatten and touch the ground you are more likely to overpronate when you run. If your arches flatten slightly but do not touch the ground, you could consider yourself a neutral runner. However, if your arches remain elevated and most of your weight rests on the outside of your feet, you are a supinator. If you have flat feet (pes planus) to start with consider yourself a pronator and if you are born with high arches (pes cavus) you can place yourself in the supinator category.
Important Tips to Remember when choosing a shoe
- Pick shoes that are appropriate for the sport you will be participating in
- Make sure the shoes are comfortable and fit properly (should be a thumbnail between your toe and the end of the shoe, your heel should not lift out of the shoe, distance between laces 2-3 cm with no wrinkles)
- Make sure shoes are flexible (bending point of the shoe should correspond to the spot where the ball of your foot would lie if you were wearing it)
- Shoes should protect from injury (ensure there are no abnormal seams, wrinkles or defects)
Don't Forget ...
Shoes lose their shock absorbing qualities after 200 - 400 miles (320-640 km). For the average runner, shoes should be replaced every 4-6 months.
Vaiva Underys BSc PT, MCPA
Printed: December 2002
Copyright ©2002 SEMI
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