Cocoa may help overweight people exercise safer

There may be a way for overweight and obese people to exercise safer without placing excess stress on their cardiovascular systems. The answer could be in cocoa! That’s according to an Australian study which suggests that consuming a beverage rich in cocoa flavanols may improve blood flow to the muscles and ease the demands on the heart during exercising.


The findings of the study were published in the British Journal of Nutrition, showing that after exercise, obese and overweight people had blood pressure levels that were 14% lower after they drank a beverage containing high amounts of cocoa flavanols (701mgs), compared to a group which drank a low flavanol drink (only 22mgs).

The high flavanol group also experienced a 6.1% increase in flow-mediated dilation…which is basically a measure of a blood vessel’s ability to relax. 

I only have two issues with this study. Firstly, there is no mention of the beverage’s nutritional ingredients or contents. What was the protein, carbohydrate, and fat percentages? What else was in the beverage besides cocoa flavanols?

My other concern is that the researchers used the BMI (body mass index) to determine which subjects were overweight and which were obese. The BMI has many flaws and I wonder why the researchers didn’t use more accurate methods to measure the subjects.

Anyway, with regards to study in general, I’m sure this doesn’t mean you can scoff loads of chocolates and expect to exercise with ease. Please use common sense before starting any exercise regime. Start off slowly and move at your own comfortable pace, before building up and increasing your speed and resistance over time.

2 Responses

Hi Stefanie

Thanks for mentioning that chocolate milk study…I remember reading about it a few years ago. You’re right, it was supported by the Dairy and Nutrition Council which immediately puts a big exclamation mark over the results.

It still baffles me why milk is consumed in such high quantities, considering that between 60% and 70% of the world’s adult population cannot effectively metabolize lactose. It’s hardly surprising that the production of lactase falls dramatically after the weaning-period in humans, suggesting that adults shouldn’t really be drinking high quantities of milk. According to the study "To meet the current recommendations for post-exercise carbohydrate intake (19, 24), a 70-kg male and a 60-kg female would need to consume 17 to 27 and 14.5 to 23 fluid ounces, respectively, of low-fat chocolate milk, depending on the brand." That’s a lot of milk!

At Xtend-Life, we encourage people to try and limit their daily intake of milk…preferably none at all. Although we understand that adding a little bit of milk to a hot beverage is enjoyed by some people.

From a physiological perspective, I personally cannot see the benefits of consuming milk (chocolate, low-fat or otherwise) to aid post-exercise recovery. Unless I’m very much mistaken, professional (or even weekend) athletes don’t look for the nearest milk carton once they’ve finished their exercise.

We’ll probably never know why both studies left gaping holes in their data…leaving more questions than conclusions. Thanks again for your comment Stefanie, I’m looking forward to hearing what other people have to say about this.

Xtend-Life Expert April 14 2010

I read a journal article some time ago titled "Chocolate Milk as a Post-Exercise Recovery Aid" by Karp, Johnston, Tecklenburg, Mickleborough, Fly, and Stager.  It was published in the International Journal of Sport Nutrition and Exercise Metabolism.  Chocolate milk, they said, had the optimal carbohydrate-protein ratio.  They used low-fat chocolate milk.  The study concluded that cyclists who drank chocolate milk performed just as well or even better on endurance tests than those who drank fluid replacement drinks or carbohydrate replacement drinks (Gatorade, etc).

I have some reservations about the study because it was funded in part by the Dairy and Nutrition Council.  (Hmmm.)  Also, there was no explanation in the article (as far as I could tell) about why they chose to use chocolate milk instead of regular milk.  Reading your post now, it seems like there could have been a good reason why they went with chocolate milk aside from just taste.  But perhaps the amount of chocolate in commercial chocolate milk was just not significant enough to produce the effects discussed in the study you mentioned? 

That said, I really would like to know as well what else was in the beverage used in the study, aside from cocoa flavanols.  Chocolate is almost always combined with an equal amount of sugar to produce a palatable drink, because it’s a naturally bitter substance.

Thanks for the thought-provoking post!

Stefanie Jacinto April 13 2010

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