Nice change from being told to GIVE UP something yummy
Some are exercised over chocolate milk study
Los Angeles Times
Mar. 23, 2006 12:00 AM
One little milk study and everyone's having a cow.
For decades, biochemists and physiologists in the dog-eat-dog world of sports drink technology have struggled to find the perfect elixir -- the right balance of carbohydrates, electrolytes, protein and fluid to keep athletes in peak form after various types of exercise.
So it was big news when exercise kinesiology professor Joel Stager and co-workers at Indiana University in Bloomington declared they had stumbled upon the perfect drink for elite cyclists recovering their energy after strenuous exercise.
That beverage was chocolate milk.
In three trials administered at one-week intervals, nine male cyclists performed a strenuous workout then drank one of three drinks. One group got standard 2 percent chocolate milk, another drank fluid- and electrolyte-replenishing Gatorade and a third group Endurox R4, a specially formulated beverage with a "patented 4 to 1 ratio of carbohydrates to protein" and other ingredients aimed at replenishing muscle glycogen stores and helping rebuild muscle.
Then, after a rest period, the cyclists exercised again, this time to exhaustion.
The study, published in the February issue of the International Journal of Sports Nutrition and Exercise Metabolism, and funded in part by the dairy industry, reported that cyclists who drank chocolate milk at the break were able to continue cycling about 50 percent longer than those who drank Endurox R4 and about equally as long as those who drank Gatorade.
The dairy industry swiftly embraced the study. A group affiliated with the nation's milk processors, the Milk Processor Education Program, or MilkPEP, issued a statement suggesting that chocolate milk had outperformed Gatorade.
Gatorade, for its part, immediately issued a spirited rebuttal of the conclusions arrived at by MilkPEP.
And Robert Portman, chief executive of PacificHealth Laboratories Inc., which manufactures Endurox R4, groused, when telephoned, of the milk industry funding: "That's like a cigarette manufacturer concluding that smoking is good for you."
Some sports nutritionists weren't surprised by the results. "I've been touting chocolate milk for years," says Felice Kurtzman, sports nutritionist for the University of California, Los Angeles' athletic department.
"Chocolate milk provides carbohydrates, calcium, other trace minerals," she says. "And the important thing is that the kids drink it. I can tell you from our training table that football drinks it, swimming drinks it, track drinks it."
At issue is which drink best supplies the body's needs to reinvigorate and repair itself following strenuous exercise.
Carbohydrates are the most important factor in the short-term for replenishing the energy after vigorous exercise, sports nutritionists say.
"The body needs carbohydrates to refuel the muscles," says Nancy Clark, a Boston-based sports nutritionist in private practice and author of "Nancy Clark's Sports Nutrition Guidebook."
But protein is also important for recovery, Clark says. It provides amino acids for the building and repair of muscle tissues.
More immediately, she adds, a little protein might give an athlete a performance edge by enhancing insulin release, which aids in the transport of carbohydrates to the muscles.
Several sports nutritionists say the study has a few limitations, including its small size.
They also express surprise that chocolate milk outperformed Endurox R4 because both contain large amounts of carbohydrates. Some said they were surprised that Gatorade did as well as it did, as it is not designed to be a recovery drink.
Still, Clark says she's happy to see chocolate milk get its due. Athletes used to thrive on real food, but now they're relying on supplements.
"I like that it brings people back to real food," she says. "Sometimes they forget that food works."
The fact that a study on milk was supported by the dairy industry isn't unusual in the field of nutrition science, in which research dollars are scarce. But the study struck a sour note with sports drinks producers, who take energy drinks seriously.
Portman, of PacificHealth Laboratories, said at least part of the results contradict the large body of research highlighting the importance of carbohydrates. Based on that criterion, chocolate milk should have been running laps around Gatorade, which has about half as many carbohydrates as the chocolate milk. And milk should have performed about as well as Endurox R4, which has components similar to milk.
Bob Murray, director of Gatorade Sports Science Institute and an exercise physiologist, objects to the inclusion of Gatorade.
"It's a matter of what the beverages were designed for," he says. "I wouldn't put Gatorade on my cereal."
Stager says he wasn't surprised at the performance of chocolate milk.
He said he first noted the effectiveness of the drink years ago as a high school athletics coach in Bloomington.
He'd noticed that some of the kids would skip lunch, which impaired their performance. One day, he introduced chocolate milk into the training regimen -- and with each glass of milk, which the kids happily lapped up, their performance improved.
"There's a truism in the world of sports science," he says, "that many times sports researchers identify things that the athletes already know."