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Neuro Athletes, 

How much do you actually know about hydration?

A number of factors can reduce your cognitive capacity. If you’re an athlete or you’re in the financial services sector, one thing is certain; you must be able to think fast and intelligently for a number of hours a day. And one thing that can prevent you from thinking optimally is dehydration.  

Your brain is a delicate system with many moving parts. When the system is balanced, life is good. But when it becomes unbalanced, there are consequences.

The balance of this system depends, in part, upon electrolytes—a handful of minerals that carry electrical charges, regulate fluid balance, and influence many other functions in your body and brain. One ramification of severe sodium deficiency, for instance, is a profound swelling of the brain. This unhappy condition is called cerebral edema.

The interesting part?

Most people don’t even know how to hydrate properly.

Neurobiology of Hydration

I’m sure you know that ~70% of our total weight is comprised of water. Well the rest is pretty much comprised of solids. We can break down the 70% water content into two categories:

1. ICF or intracellular fluid

The vast majority of the water content in your body resides inside your cells (about 66%).

1. ECF or extracellular fluid

The remaining 2/3 of the water content resides in the ECF. Both inside and outside the cells, water acts as a solvent for electrically charged molecules called ions (also known as electrolytes).

What are electrolytes?

Electrolytes are called electrolytes because they carry electrical charges between cells. In other words, these minerals facilitate the transmission of nerve impulses, immune signals, and many other communications throughout your body via a synapse (a structure that permits a neuron (or nerve cell) to pass an electrical or chemical signal to another neuron).

Neurons rely on two specific electrolytes - sodium and potassium. This is because neurons transmit signals using a flow of Na+(sodium) and K+ (potassium) ions, which produce an electrical spike called an action potential (AP).

So…

If hydration levels are too low, our neurons cannot function properly, leading to cognitive problems such as delayed thinking and reaction time, fatigue, low concentration, etc..

The main positive electrolytes are the ones above to the left while the main negative electrolytes are the ones to the right and of all the electrolytes, sodium is the most important for brain health. When sodium gets too low, a variety of symptoms result—from headache to fatigue to brain damage.

Hang on, I’m not an athlete, why do I need to know this?

Yes, I can hear you! Just because you aren’t running a marathon each day that doesn’t mean you cant be dehydrated. Where is the highest concentration of communications in the human body? That’s right. In the brain.

Every decision you make requires energy and that energy is made up of the accumulation of action potentials.

Each action potential is the result of the transfer of ions (electrolytes). So if you want to be able to think faster and for longer, in any field, you must understand the science of hydration. If you dehydrate yourself, your risk of mental mistakes increases.

Costing you millions…

Neurobiology of Dehydration

When dehydration strikes, part of the brain can swell, neural signaling can intensify, and doing monotonous tasks can get harder. An article published on Neuroscience outlined a study that was done using fMRI scans of brain regions when an individual was dehydrated.

The scans showed remarkable changes in the ventricles and thalamus.

The study’s first author said:

Hydration Protocol

Firstly, stop buying products that promise hydration in a colourful way.

There, I said it…

Countless companies have tried to reinvent water. They’ve infused it with vitamins, electrolytes, or rock salt for “better body balance.” That’s the view that gadfly scientist Tim Noakes and others have advanced over the past decade. All those high-tech promises of better or more effective hydration? It’s just marketing hype from big companies like Gatorade. Most of these products are just plain old H2O in an overpriced bottle.

Instead, follow this simple protocol that is backed by science to test your hydration and implement a strategy to rehydrate effectively.

Step 1: Measure hydration upon waking using the ‘urine test’.

Step 2: Equation for how much water to drink when doing mental or physical exercise (from @DrAndyGalpin). Body Weight (in lbs) / 30 will give you the number of ounces of water that you should drink every 20 minutes when exercising or doing mental work.

Step 3: Use salt liberally. I did a podcast with Dr. James DiNicolantonio on the mineral diet and he mentions quite frequently how we are deficient in minerals such as sodium, potassium and magnesium. Check the podcast out here

Fun fact: When we’re properly hydrated, the kidney produces between 800-2000ml of urine everyday and the urine is a pale yellow shape!

If you want to learn how to maximise on your own physiology then you want to sign up to my premium membership!

If you have information you would like to share please contact me at [email protected]

What to Read

1. Rehydration strategies--balancing substrate, fluid, and electrolyte provision (LINK)

1. Progressive dehydration causes a progressive decline in basketball skill performance (LINK)

2. Am I Drinking Enough? Yes, No, and Maybe (LINK)

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