The sweltering heat and humidity continue to bear down on the Midwest, with the heat index reaching more than 100 degrees on most days. It’s best to stay inside when you can, but that’s not always possible, even in the extreme heat. So what do you do if you have to be outside for an extended time? For answers, we checked with the team doctor of the Kansas City Royals, Dr. Vince Key, who also sees patients at the Sports Medicine and Performance Center at The University of Kansas Hospital.

In the video, Dr. Key says the number one way to stay safe in the extreme heat is staying hydrated. But he says you can’t wait till the day you’re going to be outside to start that process…you need to start three days early. He also says water is good, but it can dilute your body’s electrolytes, and he has advice on what to drink. Dr. Key also explains why nutrition is important for proper hydration, outlines tips for keeping cool and most importantly, describes symptoms and signs that you may need help from too much heat.