Sweat evaporates off our skin which allows for heat loss and cooling. However, when we sweat, we also lose water and electrolytes (i.e., “salts” such as sodium, chloride, potassium). Drinking enough water and having enough electrolytes is necessary for our bodies to function properly.  We keep hearing about this massive heat wave hitting the US.  Although, it isn’t substantially hotter than normal, it is still important to keep our hydration and electrolyte levels in check.  

Heat exhaustion occurs when a person exercises and works in a hot environment and the body cannot cool itself adequately. Dehydration occurs with water loss from excessive sweating, which causes muscle cramps, weakness, and nausea and vomiting. This makes it difficult to drink enough fluid to replenish the body’s water supply, and the lack of body water impairs further sweating, evaporation and cooling. Relative humidity is an important factor in developing heat exhaustion. If the humidity is too high, sweat on the skin cannot evaporate into the surrounding air and body temperature cooling fails. – MedicineNet

Some major sign may includes: salt cravings, extreme fatigue, loss of appetite, extreme thirst during and after workouts, mild headache, and then finally vomiting and dizziness. 

Livestrong.com provides a great explanation:

Electrolytes play an important role in the natural homeostasis of the body by maintaining a stable internal environment. They help coordinate muscle contractions, heart function and the conductivity of electric signals in the nervous system. Normally the kidney is the organ that regulates fluid absorption and excretion in order to preserve a narrow electrolyte balance, but when the level of electrolytes becomes too high or too low, an imbalance can occur. Sodium, potassium and calcium are usually the elements most likely to suffer from an electrolyte imbalance.

An electrolyte imbalance is caused by a change in the amount of electrolytes in your body. There are many reasons why these levels might change, including a poor diet, medicines, and kidney problems. Athletes, or at least anyone who exercises on a regular basis, must be acutely aware of an electrolyte imbalance because of the minerals that may escape from sweat, especially during hot days. Sweating is important for maintaining body temperature, but a few grams of electrolytes are lost for every liter of sweat.

So, what can you do to prevent heat exhaustion?

We need to make sure we hydrate properly but just water isn’t going to suffice.  We will need to include some electrolytes.  These can be found in coconut water, gatorade, or electrolytes powder.  My favorite is LMNT powder.  I get it on Amazon.