Electrolytes: Prepare for the Losses

Electrolytes: Prepare for the Losses

Most people are familiar with the word ”electrolyte,” but few understand what they really are.

Roughly speaking, electrolytes are substances that can be dissolved in a liquid and form electricity-conducting solutions. Almost all soluble salts, acids, and bases are electrolytes.

But why would you care about this in the first place?

When talking about electrolytes in the aspect of physical exercise, we usually focus on the minerals. Sodium, potassium, magnesium, chloride, calcium—all of these are electrolytes that are present in ALL cells, tissues, and liquids of the human body, in dissolved form. They take part in hundreds of processes and reactions, but here are some of the most important ones:

  • Calcium plays an important role in heart, skeletal muscle and blood vessel contractions
  • Sodium and potassium are essential for generating and conducting nerve impulses
  • Chloride is a crucial component of gastric juice
  • Phosphorus, together with calcium, is a key component of bone tissue

In other words, electrolytes are everywhere in your body, and they take part in virtually all processes you could think about, no exception.

This includes, among other things, the regulation of temperature and the control of water balance in the body.

One way in which the human body loses electrolytes is through sweating.

running man sweating
Photographer: Shashank Shekhar | Source: Unsplash

Is sweating really that dangerous for your electrolyte levels?

Can you guess the amount of electrolytes you lose at the gym?

Well, the composition of body sweat is somewhat different from one person to another, but here’s a rough estimate:

  • Sodium – 863 mcg/ml
  • Potassium – 222 mcg/ml
  • Calcium – 16 mcg/ml
  • Magnesium – 1.3 mcg/ml

Some people sweat like crazy at the gym, other folks are permanently dry no matter how much they lift but, on average, scientists estimate that people can generate up to 1.5-3 L of sweat per hour of exercising in hot environments (that’s 50-100 fl oz), or some 800 ml at room temperature (about 27 fl oz). Multiply the salt content in sweat from the short list above by the average sweating rates of most people, and here’s an estimate of the electrolytes one would lose after an hour of sweating at the gym (800 ml of sweat at room temperature):

  • Sodium – 690 mg
  • Potassium – 178 mg
  • Calcium – 13 mg
  • Magnesium – 1 mg

How much is that?

Nothing critical, really. For comparison, according to the USDA food database, one cup of cow milk (about 244 g or 8 fl oz) contains:

  • Sodium – 107 mg
  • Potassium – 366 mg
  • Calcium – 305 mg
  • Magnesium – 26.8 mg

So, a single cup of milk will restore almost all the electrolytes you would have lost through an hour of sweating. The only electrolyte left would be sodium, which can be easily restored using a bit of kitchen salt (NaCl, remember?) and any kind of food.


Do you need electrolytes in you pre-workout?

Depends on the person. Most people’s bodies are SUPER effective at controlling levels of electrolytes), but some people may benefit. Sticking to your usual meal plan would probably be enough to restore the electrolytes lost in a single sitting, and don’t forget that there’s a small amount of most of the minerals mentioned above in drinking water as well.

To summarize, don’t sweat about the sweat: you’d have to try really hard to mess up your body’s electrolytes this way.

Many pre-workout supplement brands affirm that a nice blend of electrolytes will help you avoid exercise-associated muscle cramps, which makes sense logically, but since a few Studies report that about 69% of people experience exercise cramps even when properly hydrated and supplemented with electrolytes,… Electrolytes aren’t a universal fix. Listen to your own body and decide for yourself.

-The Cost Plus Nutrition Team