If you run for fun or just to stay healthy, you probably aren't too concerned about how many miles you rack up, but you should be. Not to brag to your friends and family, but to help figure out when you need to purchase new shoes. You should be springing for new sneaks after you've completed between 300 and 400 miles.

Here are some ways to keep track:

• Wear a pedometer. About 2,000 steps is equivalent to one mile. Keep track of your miles each week by writing them down in a fitness journal.
• Use an iPod Nano and the Nike + iPod Sports Kit to track your mileage per workout. Then you can upload your data to the NikePlus.com website, and they'll keep track of your mileage for you.
• Run on a track. It's easy to know how much you've run since four laps equals one mile. Jot down your mileage each time you run.
• If you like to run outside but aren't sure how long your favorite neighborhood route is, use Google Maps Gmaps Pedometer to help you figure it out.
• Use another techy device like a handheld GPS or watch/heart rate monitor that has a mileage feature to figure out the distance you've traveled per run.

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