By day, Lisa Bliss is a physician, helping people non-surgically rehabilitate from musculoskeletal injuries. In simpler terms, she helps people get rid of their pain, which is ironic because in her spare time, she enjoys the opposite for herself. Bliss – an ultra runner in addition to being a doctor and medical director – puts herself through the ringer. The 39-year-old enjoys running distances so much, she'd prefer to do five marathons at once.