If you're not used to running on a treadmill, let me sum it up in one word for you: Boring. If there is one thing I hate, it's cardio equipment. I hate the artificiality of it. However, I've never been a runner. I find it hard to motivate myself to run for long periods of time outside, and usually have to participate in cardio activities that involve a bunch of tiny goals along the way. Hiking to the top of a mountain? Great! Climbing stairs at Harvard Stadium? No problem. Running... just as long as I can? Kill me.
That's why I've created this 20-minute treadmill workout. Not only is it convenient for all of your avid outdoor runners (now that its starting to get cold out), but it also involves a constant change in incline and speed. For me, this helps keep me focused as I look at each interval as a mini goal to complete. The added benefit is that interval training is much more effective for metabolic conditioning than running at one speed or incline for the same period of time.
I've included incline options for two levels as it's important to go at your own pace. Respect your pace and remember to adjust speed, incline, and duration as needed. After you try it, let me know how you like it in the comments below!