Maintaining hydration as a runner is important for health and performance. Water regulates our body temperature, removes waste, helps brings energy to our cells, and cushions our joints. Adequate hydration can improve recovery, minimize injury and cramping, and maximize performance.
When we run, we generate twenty times more heat than when we are at rest. We avoid cooking ourselves by sweating, which cools our bodies. However, sweating also leads to loss of water and electrolytes, including sodium and potassium. In fact, losing more than two to three percent of our body weight through fluid (3-5 pounds for a 150-pound person) can lead to dehydration. When we are dehydrated, we may be tired, get headaches, cramp, and have an increased heart rate. Performance can suffer.