If you or your running partner can hear your footsteps clearly, you may want to try to run more silently. Loud footsteps are heavy footsteps and are an indicator of poor running efficiency and the potential for injury.
When I run, the sound of my breathing is much louder than the sound of my feet. I often startle people when I come up behind them, because they don’t hear me coming. I have to clear my throat as I approach them, so that they don’t jump as I pass them.
If you have loud footsteps, make sure you aren’t overstriding, landing on your heel, and “slapping” the ground with your feet. This is a common problem on downhill runs, but some people do it on the flats as well.
You want to make sure that your ankles are relaxed and flex to accommodate your foot striking the ground. You should always feel that you are pushing the road backwards with the soles of your running shoes, like a giant treadmill. You shouldn’t feel any “braking” action and it shouldn’t feel like your foot is sliding forward in your shoe.
Make sure you aren’t lifting your feet too high, bobbing up and down, or swaying from side to side. You want all of your motion to be in line with the direction you are running in.
Try to run as quietly as possible for a short distance. Gradually increase it as you get better at doing it. I think you will notice an improvement in your running form and efficiency.
Another way to learn to run silently is to run barefoot or in minimalist shoes like the Nike Free or the Vibram Five Fingers. Slapping the ground hard with bare(ish) feet will hurt and you will stop doing it in a hurry. As always, take care not to overdo it and get injured.
Let me know how this impacts your running in the comments.