Q: (from the email bag): I have a question about shoes. I bought my current pair in early January. I've worn them for all my marathon training, putting on about 450 miles. On my last long run, my legs felt achy; they did not feel right.
My marathon is in 4 weeks. Should I get a new pair to race in? Should I consider going with a racing flat? I have run marathons in flats before and am wondering if it would be worth it in this race. There is a weight difference for sure.
A: Good questions. Surprisingly, there is no consensus as how many miles you can safely run in a pair of shoes.
An 18 year long study lead by Ewald Max Hennig of the Biomechanics Laboratory at University of Duisburg-Essen in Germany indicated that shoes could be safely worn for more than 600 miles/960km! In a survey of running literature, most articles recommend changing shoes every 300 -- 500 miles (480 -- 800 km).
The distance you can safely run in a pair of shoes depends upon many factors. The surface you run on, your weight, your biomechanics, your running-specific strength in your feet and lower limbs, minimalist shoe vs. traditional shoe are some the variables affecting shoe life.
What to do?
Listen to your body carefully. You should suspect that you are running in shoes that are past their “best before” date if they don't feel the way they used to. You may intuitively know something does not feel right. You may feel like your legs are absorbing more shock. Your legs may feel achy or sore. You may feel unusual slight twinges that you are unaccustomed to.
Ann, your current shoes have served you well. Your legs are telling you that it's time to retire your shoes. Unfortunately, four weeks is not a lot of time to break in a new pair of shoes. If you stick with the identical model, your new shoes should be adequately broken in for race day. Make sure to run at least one longish run (15K) in them. Keep your current pair just in case your "break in" plans hit a snag.
I advise against racing a marathon in racing flats, unless you have already completed two long runs (20 miles/32 Km or longer) in them. What you gain in speed due to reduced shoe weight is more than offset by reduced stability and/or shock absorption. Racing a marathon in racing flats without being fully accustomed to them for long runs is courting race day disaster.
The best shoe replacement strategy?
When training for a race, buy a new pair of shoes two months prior to your race. Gradually break them in. Wear them first on short runs only. Anyways, it's a good idea to have two pairs in case one gets soaking wet and hasn't dried out in time for your next run.
Come race day, you'll be able to choose in which pair you'll shine.
Lastly, please donate old shoes to a worthy cause.
How do you know when it's time to retire your shoes?
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Bennett Cohen and Gail Gould are the Founders and Presidents of the International Association of Women Runners. For access to resources to help you reach your goals for running and racing, visit www.IAWR-Connect.com..