If you typically run outdoors, it's probably a good idea to use a treadmill every now and then -- along with a full-length mirror close by. By observing yourself in the mirrors at the gym, you can better evaluate your form and make adjustments where needed.

Perhaps surprisingly, running form is largely dictated by what you do ABOVE the waist. Here are a few things to look for:

  • Your back posture should be perfectly straight (no slouching).
  • Your head should be in a neutral and comfortable position; you should not be looking up or down. Rather, you should be looking straight ahead.
  • Your arms should be bent at a 90 degree angle. They should swing back and forth casually at your sides as you run. Don't waste energy on clenched fists.
  • Your hands should be lightly clenched, as if you were gently holding fragile object in each one. Hands should face inward toward your body, not downward.

Ideally, by improving the subtleties of your form in the mirror, you'll be better able to continue them when you hit the open road.