Coconut Water for Rehydration When I was in Costa Rica this last April, one of the locals I was riding with suggested we stop and have a drink of fresh coconut water. Coconut water is basically the juice from the inside of a young coconut, before that juice becomes coconut milk. To have a taste of the stuff, we simply stopped by a roadside fruit stand, and the owner knocked a whole in the coconut and gave us a straw. The coconut water had an interesting taste, very mildly sweet, and refreshing. As we sat next to our bicycles, the local rider started telling me how coconut water was a perfect rehydration drink. He went on about how coconut water was isotonic, meaning it has the same electrolyte concentration as the blood, and that it was actually used as IV fluid in place of saline during WWII. Those that know me, know that I consider myself and “open minded skeptic” when it comes to this sort of thing. Honestly I thought the local guys was probably full of it, but I was still intrigued and I decided I would investigate further when I returned home.
What I found out actually surprised me. Not only was coconut water isotonic to blood, but it was really used in WWII and there were several journal articles reporting the emergency use of coconut water being successfully used for IV hydration in place of saline. Another study suggested that coconut water was just as effective as a commercially available carbohydrate/electrolyte beverage in rehydrating subjects, and the subjects actually had an easier time drinking the coconut water. Now I had to go find myself some coconut water. ( There are no roadside fruit stands with young coconut near my house).
They don’t have the stuff at the Vons supermarket around the corner, but I found some at the Pancho Villa Market just a few minutes away.
The coconut water I found was 70% percent coconut water ( juice) by volume, with 30% added water and a little sugar. 12 oz of plain coconut water would have about 70 calories, but the added sugar brings the calorie count of the stuff I bought to about 110 calories per can. This is still a little bit more than calories than Gatorade, and about 1/3 less than a can of soda The extra sweetness is not unpleasant after a long hard ride in the heat, but I wouldn’t be opposed to have the unsweetened stuff either. It is actually quite easy to buy canned, unsweetened coconut water online, so I'll probably order some soon.
Physiologically I wouldn’t say its “perfect” as an electrolyte replacement drink, as the sodium is a bit low (it has about half as much sodium as the same volume of Gatorade). But then again it is packed with potassium and you are most likely going to get plenty of sodium from your post exercise meal. it is really a little low on sodium for use during exercise, but is pretty good as a post exercise drink. Some studies have even shown that potassium is highly important for maintaining proper blood pressure and heart health, so the extra potassium could be a bonus.
My personal verdict? My fridge is almost always stocked with a few cans of coconut water these days. It has become my go to beverage when I get home from a long ride. It tastes good , gives me a few carbohydrates, and replaces some of those lost electrolytes.
So now is the time where I give you my shameless plug for your chance to try FRESH coconut water. We are going to have a Crank Cycling training camp in Costa Rica this February. It will be a weeklong camp where you can ride every day, relax by the hot springs each night, and sip fresh coconut water straight from the coconut. Stay tuned for details.