In these incidences, I have learned (again from triathlon pro Jessi Stensland) that you should do the following:
1. Position the treadmill incline button to 2 percent to simulate outdoor road conditions. (I also use the "Hill" workout as another option.)
2. Stand and run upright, keeping your core firm.
3. Keep your foot directly under the hips.
4. Neck, shoulders and back relaxed. Arms by your side, fingers relaxed, not tightly clenched.
Treadmills are a great place to work on cadence. Try and keep your strides light, running on the ball of your foot, turning over quickly. Another good treadmill feature is that you can hear yourself run -- whether you are landing light or heavy on your feet. Try and tweek your run until you hear the beautiful sound of quiet, efficient running mixed with the whizzing hum of the treadmill. And if you can pop in a good movie at the same time, all the better.