Have you ever woken up and groaned as you fought with yourself to get out the door to run? You are not alone. That is in our biology. We evolved to want to conserve energy. The idea of exercising is only something that we've been doing relatively recently. Dr. Daniel Lieberman's new book, Exercised: Why Something We Never Evolved to Do Is Healthy and Rewarding is a great read. Evolutionary biologist, Dr. Daniel Lieberman joins us to discuss what this means for us as passionate runners. Dr. Lieberman wrote the 2004 article, Born to Run: Here is the video Dr. Mark Cucuzzella mentioned. Please check out Dr. Mark's running store, Two Rivers Treads and his podcast.