Salt, Sweat, and Hydration: Dr. Patrick Burns  Should you be taking sodium and other electrolytes while racing? What are electrolytes anyway, and what are the key factors that affect electrolyte levels when running? Dr. Patrick Burns has been studying the answers to these questions and more, and shares his latest research in this episode.   Patrick started running as a Massachusetts high school student. He traded short distances for the two-mile event after discovering he was “not fast.” At Bowdoin College in Maine, he made another switch, favoring enjoyable and exploratory running over competition. This continued as he traveled the world as a nomadic teacher, using running as a way to explore new countries.    Eventually, Patrick moved back to be near his family and go to Tufts medical school. His sister, Katie, had six marathons to her credit, and Patrick decided to train with her for one. This is when he really fell in love with running. Patrick and Katie completed the Boston Marathon, and more long distance races followed. However, once he began his Emergency Medicine residency at the University of Washington, Patrick had very little time to run.    Four years later, Patrick did a Wilderness Medicine fellowship at Stanford. Here he discovered RacingThePlanet and ultramarathon running while working as a researcher on a race in Ecuador. He was hooked. Here’s Patrick’s definition of Type 2 fun: a self-supported, 250 km, 7-day race through extreme environments. He considered this brutal, grueling, and amazing.  Patrick is currently a clinical assistant professor for the Department of Emergency Medicine at the Stanford University School of Medicine and the assistant director of the  Wilderness Medicine section. He continues to work with RacingThePlanet to answer questions related to ultrarunning.  This project coincided with his first RTP ultramarathon – a fantastically humbling experience.   Questions Patrick is asked:   2:35 You are an ultra runner and emergency room doctor at Stanford University and before I get into the main topics that I'd like to discuss today, how is the current situation there?   3:15 Stanford is now doing all their classes online. Is that correct?   3:59 As we head into the summer months in the northern hemisphere, many athletes become more concerned about electrolytes.  You are one of the authors of a very interesting study on hydration and electrolytes and you were also one of the test subjects.  Before we get into the study, can you give us a little primer on electrolytes, what they are, and why they are important for the human body?   4:56 What happens when you run long distances and get those electrolytes out of balance?   5:54 Can you explain what hypo- and hypernatremia are and why that matters?   6:23 Can you talk about some of the complications of hypo- and hypernatremia?   9:00 Is hyponatremia more dangerous than dehydration or hypernatremia?   9:34 Is sodium the most important electrolyte?    9:54 Are some electrolytes more important than others?  Do you have to replace all of them while racing?    10:31 Can you describe the study that you and your colleagues did?  What was the goal of the study?  How was it conducted?     13:12 How many people raced in the event and how many people did you end up studying?   14:40 How were samples collected? Were you pricking people’s fingers?    16:12 How good are we at hydrating and keeping sodium levels in balance?   16:54 Is a too high sodium level from taking in too much salt or not taking in enough water, or could it be either or both?   17:44 Did you talk to the runners in the study about why they were doing what they were doing with regards to sodium? Why is there such a big range of what we take in?   20:08 Should you change your sodium level intake in a hot race?   21:34 Do you have any insight on taking extra electrolytes for muscle cramps?    23:13  I would love to ask you about the drink-to-thirst philosophy. We’re reading a lot about that nowa