Chocolate Milk as a Post-Exercise Recovery Aid
In a study that compared the effectiveness of chocolate milk, a fluid replacement drink, and a carbohydrate drink as post-exercise recovery aids, a group of endurance-trained cyclists were put through daily regimens of an interval workout followed by a four hour recovery period, followed by an endurance trial to exhaustion at 70%  
 VO2max.
After the first two hours of each recovery period, the athletes drank equal volumes of either chocolate milk, the fluid replacement drink, or the carbohydrate replacement drink in a random, single-blind experiment*.  The cyclists who drank the chocolate milk or the fluid replacement drink were able to bike nearly twice as long in the endurance trial before reaching exhaustion than those who consumed the carbohydrate replacement drink.  The result suggests that “chocolate milk,  with its high carbohydrate and protein content, may be considered an  effective alternative” to commercial sports drinks.  The researchers note that “the carbohdrate in chocolate milk is composed of sucrose (glucose plus fructose), lactose (glucose plus galactose), and high fructose corn syrup.” 
Apparently, the absence of sucrose in carb replacement drink in the study contributed to the shorter time to exhaustion and less total  work.
Reference:  International Journal of Sport Nutrition and Exercise Metabolism, 2006, 16, 78-91
*The subjects could probably taste what they were drinking.
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