Coconut Water Benefits for Runners
Here’s what you need to know about coconut water, hydration, and re-balance electrolytes during exercise.
Everyone knows that hydration plays a big part in training performance and recovery.
Yet, what is it exactly why we need to re-hydrate, and what are the best ways to do it?
Is coconut water really superior to plain water (or other hydration options)?
LAST UPDATED: March 2019 by Ben.
Author: This article is written by Nicola Joyce who is a a member of the National Union of Journalists and has been a competitive athlete for a number of years.
This review of coconut water is supported by cited references.
Good hydration means striking a balance between over-hydration and dehydration.
A lot is known about the latter (you’ve probably felt the brain fog, poor gym performance, and cramps that come with being dehydrated).
However, over-hydration can be just as problematic, even leading to hyponatremia where your body’s electrolytes are diluted by too much fluid.
There have been cases whereby contestants for game shows have literally drank themselves to death for prizes. 
Accidental death aside, in essence, being well hydrated means having enough fluid and electrolytes in your body to perform well and feel good.
Why We Need More Than Water For Hydration
When we sweat, we lose more than water.
So it is important to stay hydrated with specific drinks or hydration products that replace the electrolytes our bodies excrete through sweat, too.
The main electrolytes are sodium, phosphate, chloride, potassium, calcium, and magnesium.
Sodium is lost in the largest amount (between 200mg – 2000mg sodium per liter of sweat) But all electrolytes are important – they even help our muscles contract.
Sodium and Other Electrolytes
Electrolytes are chemicals that form ions in the body, and help various systems run smoothly (nervous system, cardiovascular, muscular, and digestion).
Think of electrolytes like oil to a car engine, and a car engine needs regular oil top ups.
They are not fuel, but they are critical to everything running together smoothly.
Calcium is the most abundant mineral in the body, and plays a key role in normal heart rhythm, nerve transmission, and muscle contractions.
Magnesium is crucial for converting fuel to muscular energy, and deficiency can lead to muscle cramps and poor sleep.
Potassium is the main positively charged ion in muscle cells, and sodium is the main positively charged ion outside muscle cells.
Finally, chloride is key for maintaining osmotic tension in blood and other bodily fluids.
Is Coconut Water Good For Hydration?
Coconut water has always been promoted as a good option for natural hydration.
But how does it measure up?
Coconut water is the liquid from the inside of the young green coconut which is harvested at about 6 months.
As the coconut matures the water turns into coconut flesh.
That means coconut water contains around 45 calories, 11g carbs, 70mg sodium and 500mg potassium per cup.
Compare this to plain water and to intra workout and sports hydration drinks.
Thus, you will see that coconut water offers comparably high levels of potassium – one of the important electrolytes – but falls short on others.
However, does that mean we should write it off?
Coconut Water Hydration Studies
Here is a very early study conducted on the effects of coconut water…
This 1979 study looked at coconut water as a re-hydration option following a cholera epidemic in the Gilbert Islands in the Pacific Ocean.
Compared to oral re-hydration fluids, coconut water was found to have adequate potassium and glucose content.
Yet the coconut water was found to be relatively deficient in sodium, chloride and bicarbonate. 
This more recent 2002 study compared the effects of coconut water with bottled water and sports drinks on re-hydration after exercise (in healthy young males) and found no significant differences between the three.
However, it did suggest that the coconut water may be easier and more pleasant to drink in sufficient quantities, stating that coconut water…
“caused less nausea, fullness and no stomach upset and was also easier to consume in a larger amount…” 
This contemporary 2012 study also compared the effects of coconut water with bottled water and sports drinks on re-hydration in male athletes.
It found that there was no significant difference between coconut water, sports drinks, and plain water when it comes to hydration, stating that…
“little difference is noted between the four tested conditions with regard to markers of hydration or exercise performance…” 
With those studies in mind, you would think that the conclusions were there and that was that.
Yet, the world of sports science was not just finished there though, they wanted more…
So, in 2007 another study took things a little further, by looking at the efficacy of coconut water with added sodium, compared to sports drink.
This study concluded that both the sodium-rich coconut water and sports drink hydrated better than plain water, and that the coconut water blend did a comparable job to commercial sports drink. 
So what does this all mean for your next hydration drink purchase?
Should you stick with your intra workout drink?
Buy a sports drink?
Go with coconut water (with or without added sodium)?
Or is plain water enough?
Benefits Of Coconut Water
As a natural drink, coconut water has a number of potential benefits:
- – Reducing blood pressure
- – Boosting gym performance
- – Supporting energy levels
- – Lower carbs and sugar (than most intra workout options)
How To Use Coconut Water
You can drink coconut water straight up (it’s best served cold or over ice).
But you could also add it to smoothies, add it to homemade vegetable juices, or combine with juice for a twist on your favourite fruit juice drink.
The Best Choice For Hydration
Since individual electrolyte and hydration levels vary so much from person to person, it makes sense to choose your re-hydration strategy to suit your body, mass, weight, and activity level.
Furthermore, most of us get enough sodium from our food.
So, unless you are doing intense workouts of over one hour in very hot or humid conditions, plain water will likely be sufficient.
However, if your workouts are long, intense, and sweaty then you could definitely add coconut water into your intra-workout strategy.
But remember that it contains less sugar and sodium than most sports drinks, and you may need both the extra carbs and sodium if you’re working out for that long.
So, the studies do prove that using coconut water for hydration is a good option – and it will give you added vitamins and micro-nutrients that regular sports drinks will not.
If you like the taste, by all means add it into your diet, and some supplements include coconut water extract to provide the extra benefits.
Additionally, if you are particularly looking to boost your potassium levels to prevent muscle cramp, coconut water would be a good shout, it is something I have used while playing rugby to suppress cramp.
But don’t forget the other natural sources of potassium, too: bananas and potatoes are both valuable sources, although they are not quite as convenient to have beside the sports field.
 Coconut water as a rehydration fluid. Kuberski T, Roberts A, Linehan B, Bryden RN, Teburae M. N Z Med J. 1979 Aug 8;90(641):98-100. PMID: 290921
 Rehydration after exercise with fresh young coconut water, carbohydrate-electrolyte beverage and plain water. Saat M, Singh R, Sirisinghe RG, Nawawi M. J Physiol Anthropol Appl Human Sci. 2002 Mar;21(2):93-104. PMID: 12056182
 Rehydration with sodium-enriched coconut water after exercise-induced dehydration. Ismail I, Singh R, Sirisinghe RG. Southeast Asian J Trop Med Public Health. 2007 Jul;38(4):769-85. PMID: 17883020