November 16, 2007, Newsletter Issue #79: Know When to Replace Your Shoes

Tip of the Week

Running shoes wear out – but it's not obvious when they do. By the time most running shoes' soles show significant wear, it's long past the time to replace them. Here's why:

The midsole – the shock absorbing layer of a shoe – of most running shoes is made either partly or entirely of a dense foam called EVA (ethylene vinyl acetate). Each time your foot lands, it compresses the EVA - which absorbs much of the shock - and then the EVA re-expands when you take your weight off the shoe.

You know how Homer Simpson's couch has a depression where he sits? Well, that's what happens to EVA over time: It loses the ability to bounce back. You don't notice it, because it happens very gradually. But every footfall reduces the foam's effectiveness.

By the time you've used a pair of shoes for 300 – 500 miles, the foam has lost enough “bounce” that the shoes should be replaced. Typically, lightweight runners can go closer to the 500 mile mark, while heavy runners will have to replace their running shoes at closer to 300 miles.

About LifeTips

Now one of the top on-line publishers in the world, LifeTips offers tips to millions of monthly visitors. Our mission mission is to make your life smarter, better, faster and wiser. Expert writers earn dough for what they know. And exclusive sponsors in each niche topic help us make-it-all happen.

Not finding the advice and tips you need on this Running Tip Site? Request a Tip Now!


Guru Spotlight
Heidi Splete
Buy My Book