Exercising in old or worn out shoes can lead to an increase in sports-related injuries. Over time, athletic shoes become more unstable and lose shock absorption capacity. When this happens, the stress to your feet and legs increases dramatically, and that added stress can lead to an overuse injury. A simple prevention strategy for this type of injury includes replacing your exercise shoes when they being to show signs of wear.
The midsole layer of a shoe provides the cushioning and stability. This area typically wears out before the outsole shows major signs of wear. When a midsole wears out the shoe loses its functional stability, thereby putting your foot, ankle, knee and other joints at a greater risk of injury.
It is recommended that you replace athletic shoes roughly between 350-450 miles; this is dependent on different keys, including your running or walking style, body weight, and the surface on which you exercise. Lighter runners can get closer to the upper end of the recommendation, while heavier runners are typically harder on shoes and should consider replacements closer to 350 miles.
Replacement Tips
Track your mileage; dependent on your effort and body weight, after 350-400 miles it’s probably time for a new pair. For example, athletes who run 25 miles per week (or roughly 3-4 miles per day) will need to replace shoes every three to four months.
You can check for signs of wear on the sole by placing your old shoes on a table and looking at them from behind. If the soles are worn and leaning to one side, the midsole cushioning is most likely worn as well.
Spotting Midsole Wear
A shoe’s midsole cushioning may be worn out long before the tread shows signs of wear. Because the bottom and tread of the shoe may look fine, identifying when the cushioning wears down is a little more difficult. Here are a few tips for identifying midsole wear:
First, pay attention to how you feel. As your shoes begin to give out, you may begin to get some aches or pains in your bones and joints. You may also notice slight muscle fatigue, new tightness, or possible shin splints. Take any and all of these as signs that it may be time to replace your athletic shoes.
Look for creasing of the midsole material in areas of high load. These areas are found under the heel, or near the ball of the foot. A worn out midsole will have wrinkles and creases there, which is another indication the shoe is being stressed beyond its capacity, thereby potentially hurting your feet and joints.
Try to twist the shoe. A worn out midsole will allow the well-worn athletic shoe to twist more easily than a new shoe.
Try on a new pair of the model that you are currently wearing. Compare this to your current shoes. If the cushioning in your shoes feels dead in comparison, it probably is – take the comparison test a sign that it may be time for a new pair of athletic shoes.
Consider Rotating Shoes
If you walk or run quite frequently, it’s a good idea to use more than one pair of shoes. Think about buying two pairs at a time – or, buying a second pair about midway through the life of your first. Add the new pair in to your shoe rotation when your “old” shoes have about 200 miles on them. If you use two pairs of shoes, you should still track mileage per shoe, and replace each pair after they reach the 350-450 mile point in time.
Conclusion
Take care of your feet. Wearing down your feet directly correlates to wearing down your ankle joints, your knees, and in short order, your hips and lower back. If you are a frequent runner or walker, especially on asphalt or any other hard surfaces, you owe it to yourself to look after your feet and legs – and that care begins with a properly-fitted and properly-padded pair of shoes.
