Hyponatremia -- a dangerously low sodium level -- is a risk for ultramarathon runners who drink too much water in an effort to avoid dehydration. It's a serious condition that can lead to seizures, coma and death. Some extreme athletes believe that drinking beer can help alleviate a low sodium level by causing the body to get rid of fluids through urination. So an emergency physician at Upstate who has expertise as medical director for a variety of endurance events around the world decided to conduct a study. Jeremy Joslin, MD, explains what he learned from runners at a 100-mile race in Florida. Many athletes are meticulous about the amount and type of fluids they ingest before, during an after their events. Joslin's guideline is simple: "Drink if you are thirsty," he says, urging athletes to listen to their bodies. "Your body actually knows what it is doing."