Many people run for exercise and this is a good way of burning calories as well as hardening your body. Running uses many of the different parts of the body, however if you run the wrong way it can cause injuries such as shin splints, plantar fasciitis and hamstring pain. Once, these injuries were an accepted part of running and no one thought they could be avoided by running a different way.
Runners often push off with one foot while stretching their other leg as far to the front as possible. This is not good for their balance; the reaching foot will come down heavily and must stay on the ground absorbing the weight of your body as it catches up. If you can hear your feet slapping the ground hard as you run, you may be using this technique.