In this video, Scott Colby shows you a four minute workout that will get you in great shape. All you need is a hill and some tennis shoes as simple as that. He shows you different exercises you can do, all going uphill. A few examples of the different exercises are sprints, walking push-ups, and bear crawls. The object is to continuously do them uphill then walk downhill, kind of like a circuit training. If you follow this routine you should most certainly get awesome results!