Bowl or Bottle? New Study Says Cereal Beats Energy Drinks After Exercise
What do you reach for after exercise? A bottle of Gatorade, perhaps? If so, you are not alone. Energy drink sales in the U.S. are rising 12 percent annually, expected to top nine billion dollars by 2011 (that's up from 1.2 billion in 2002). At a cost of around two dollars per bottle, these drinks quickly add up. Many of these drinks are carbohydrate-based, offering a pick-me-up post-exercise to get you feeling replenished. But given the expense, are they worth it? Researchers at the University of Texas, Austin set out to find out.
The team of researchers, led by Lynne Kammer, studied 12 trained cyclists (eight men and four women). The subjects fasted for 12 hours and then, first thing in the morning, reported for a stationary bike ride at a moderate intensity for two hours. The idea was to simulate the actual conditions under which people exercise, which are typically longer and less intense than the wild bouts of exertion usually used to bring subjects' energy stores down in prior experiments. After cycling, subjects were given either a carbohydrate and electrolyte-based sports energy drink or a bowl of whole-grain cereal (namely, Wheaties) with non-fat milk.
The researchers were monitoring their subjects' glycogen uptake and protein synthesis. As the study authors write, "Following exercise, acute physiological changes occur in the muscle that promote glucose uptake, glycogen accumulation and protein synthesis, but optimal replenishment of the energy stores and net protein balance are dependent on post-exercise nutritional content and timing." So what you eat and when after exercise matters. Why compare an energy drink with cereal and milk? Because, as the authors explain, "While glycogen synthesis requires glucose, protein synthesis requires amino acids. Combining carbohydrate with protein increases...both glycogen and protein synthesis, suggesting that the ideal recovery food must contain both carbohydrate and protein to provide substrate for glycogen synthesis and achieve net protein balance." In other words, your energy drink just doesn't have the right balance of nutrients to restore your muscles.
And, in fact, this is exactly what the study found. "Our goal was to compare whole grain cereal plus milk—which are ordinary foods—and sports drinks, after moderate exercise," said Kammer. "We wanted to understand their relative effects on glycogen repletion and muscle protein synthesis for the average individual. We found that glycogen repletion, or the replenishment of immediate muscle fuel, was just as good after whole grain cereal consumption and that some aspects of protein synthesis were actually better." In short, the study's contention is that real-life testing conditions and actual food give a better picture of the body's needs regarding post-workout nutrients. It's back to basics, and the bowl of Wheaties.