Hydration Basics


We hear it all the time: Make sure to hydrate, make sure to drink water! But why is hydration important when you’re trying to “sweat it out?”

The basic answer is simple. When you work out, your heart rate rises, causing a bump in your body temperature. That temperature increase causes your brain to send neurological signals to your sweat glands, telling them to get to work. Your body produces sweat. The process of sweat evaporating off the skin removes heat from the skin, which in turn helps cool the rest of the body (remember, your skin is the body’s largest organ!) The more your internal body temperature increases, the more you sweat. Your body needs to pull that fluid from somewhere – and some of it comes from the fluids surrounding your cells, which negatively affects cell function.

The increase in core body temperature comes more quickly and becomes more extreme on a very hot or humid day. Additionally, humidity stifles the sweat evaporation process, throwing a wrench into the wheels of your body’s climate control. And remember, you still sweat when it’s cold out. While you might not sweat as much, you still need to make sure you’re hydrated. According to our friends at NUUN:

“When you’re cold, your body attempts to preserve heat by lowering your sweat rate. But cold temperatures also mean laying up. The additional layers raise your skin temperature and can actually lead to a higher sweat rate. To balance the cold weather and your body temperature, shed layers after your warm-up but keep your extremities (feet, ears, hands) covered and warm.”


It seems a little gross, but the easiest way to gauge whether you’re properly hydrated or not is when you’re in the bathroom…and don’t wait until you’re thirsty to start sipping! Try and sip water all day to maintain proper hydration. Some great electrolyte drinks can not only jazz up your water but also replace electrolytes and nutrients lost when you sweat. Check out Nuun electrolyte replacement products, which are available in Marathon Sports stores.