This blog is dedicated to the novice and the elite triathlete in Carlsbad and the rest of North County San Diego that run under the beautiful Southern California Sun. Many people do not realize the importance of remaining hydrated when exercising. When your mouth feels like a desert it is obvious that some sort of liquid refreshment is needed. You shouldn’t wait until your tongue is so dry it sticks to the roof of your mouth, however, before replenishing fluids.

There are many factors that influence the amount of water you lose when exercising. The type of clothes we wear, the surrounding temperature, the duration of activity, our body mass, and metabolism all contribute to our personal amount of sweat production. While it’s probably a given that running a 25 mile marathon will produce more sweat than playing a game of backyard football, hydration is still essential.

Sweating is very important as it releases toxins that build up in our systems. It also cools down the body by regulating our temperature. Moving causes the muscles to exert themselves which causes the temperature to rise. We all know of people who do not seem to sweat much (or rather just glisten) and those people are more prone to overheating and not having the endurance as those who easily sweat.

We should replenish the fluids we lose ounce for ounce, which can be difficult to determine. Athletes that train for hours can sweat from 1 to 2.5 liters an hour, and even up to 3 if the training takes place in a hotter environment. That is at the minimum of 4 cups of sweat per hour. This article demonstrates the actual calculations used to determine the amount of sweat needed for least amount of cooling for intense workouts and exercise.

The body can withstand a 2% fluid loss if the temperature is lower. In hot environments, a 2% fluid loss can be a health risk causing dehydration – which can result in headaches, dizziness, nausea, vomiting, and cramps at the minimum. Our thirst mechanism, unfortunately, is a bit lazy and does not have the gumption to drink as much as we lose, so sometimes we need to force ourselves to hydrate.

When we sweat, we also lose electrolytes.  Electrolytes are, simply put, salt ions. Some ions are negatively charged, while others are positively charged. The body uses these ions to carry electrical impulses around the body. It’s akin to the body being run by rechargeable batteries. When the batteries are drained (sweated out) they need recharged.  Drinks such as Gatorade, Powerade, and Allsport contain some added sodium to replenish electrolytes.

It is important to note that drinking too much of just water can actually be harmful to the body when exercising. While drinking water daily is a great habit to start and maintain, those who exercise often, or intensely, can cause an imbalance in the system if they do not need to supplement water with a drink that replenishes the sodium we lose in our sweat. Disclaimer: the water you drink daily for your health does not count towards the water you need to rehydrate when being active.