1. First, always listen to your body. If your joints or feet are starting to hurt, that could be the number one sign you need to replace your running shoes.
2. A general rule of thumb is every 300 to 500 miles. Many factors come in to play though: your weight (over 200lbs would be closer to 300 miles); the quality of the shoe; and if you wear them walking around for normal day use (those miles count too!).
3. Check the tread on the bottom. It is usually a good indicator if the soles of your shoe are starting to lose cushioning.
4. Piece of advice - make a note in your phone when you purchase your shoes so you can average out when you will be due for a new pair.
5. Remember, new shoes are not going to cure an overuse injury, but they could prevent them. Don’t put it off, your feet and potentially the rest of your body will thank you.