Q & A with Pacers Training

Question: When Should I Replace My Running Shoes?

Answer: Running in old or worn-out shoes is one of the most common causes of running injuries. Your running shoes lose shock absorption, cushioning and stability over time. Continuing to run in worn-out shoes increases the stress and impact on your legs and joints, which can lead to overuse injuries.

So how do you know when it is time? Don't use the treads of your shoes to determine whether you should replace your shoes. The midsole, which provides the cushioning and stability, usually breaks down before the bottom shows major signs of wear. If you've been feeling muscle fatigue, shin splints, or some pain in your joints -- especially your knees -- you may be wearing shoes that no longer have adequate cushioning.

A good rule of thumb is to replace your running shoes every 300 to 400 miles, depending on your running style, body weight, and the surface on which you run. Smaller runners can get new running shoes at the upper end of the recommendation, while heavier runners should consider replacement shoes closer to the 300 mile mark. If you are a road runner you will need to replace shoes sooner than treadmill runners.

Mark your calendar when you buy a new pair of running shoes so you remember when to replace them. Other ideas include recording the date in your running journal or writing the purchase date on the inside of each shoe's tongue.