On the days when you can't run outside or you don't have time, the treadmill is a viable option, and the quality of the training is right there with a run on the road. One great benefit of the treadmill is that it has a soft surface. Your legs take a pounding on asphalt, the most common running surface, so you might even schedule a treadmill run once every week or two just to give your legs a break.

Bear in mind that there may be an adjustment period at the outset of your treadmill training. For starters, there's the speed factor. What seems to be a very quick pace on a treadmill may be a lot slower than you think it is. It is also a different feel from the road.

You can adjust the incline of your treadmill to make your session more like a hill workout, and you can preset some treadmills to vary the speed and incline to simulate realistic, outdoor conditions. To combat boredom, you can set up a television near your machine or wear earphones to listen to the radio or recorded music. Podcasts and audio books are also possibilities. The treadmill is one venue where it is safe to wear headphones.