Dean Karnazes had a corporate job. Then, on his 30th birthday, he made a life changing decision. He gave that job up. Now he's 58, a full time runner (known as the Ultramarathon Man). He once ran 50 full marathons in 50 states in 50 days. He talks about that decision, his new book, 'A Runner's High,' and how COVID has impacted his routine.