Study Links Weight Gain With Skimping on Calories
Working hard and eating lightly all day, and saving the big meal for the evening, may make an athlete more readily store fat, a study indicates.
Athletes who skimp on calories may be training their bodies to get by on less energy, and therefore to save unburned calories as fat, a researcher said.
“We can predict body fat percentage simply by the degree of the energy deficit accumulated during the day,” said Dan Benardot of Georgia State University.
“These data should discourage athletes from following restrained or delayed eating patterns to achieve a desired body composition,” the study said.
The conclusion draws some opposition from other researchers.
Benardot and his colleagues studied 42 gymnasts with an average age of around 15, and 20 runners with an average age of almost 27. All were female, and all were among the best in their sports, said the study published in the American College of Sports Medicine journal, Medicine and Science in Sports and Exercise.
The researchers had the athletes recall virtually on an hour-by-hour basis what they had eaten and what exercise they had done. The data were fed into a computer program that spit back an hour-by-hour breakdown of whether they had stored more calories than they burned, or were burning more calories than they had stored. Researchers also measured the athletes’ body fat.
Athletes who consistently burned more calories than they took in tended to be the ones with the most body fat, and those who stayed closer to caloric balance during the day tended to be leaner, the study found.
Because the study was designed primarily as a 24-hour review, it did not measure possible body fat or weight changes as a result of repeated days of light eating coupled with nights of heavy eating.
But the findings suggest that the body responds to consistent caloric deficits during the day by husbanding its resources, slowing the resting metabolic rate--essentially getting by on less energy, Benardot said.
When the athlete has a big meal at the end of the day, the excess calories have to be disposed of in some way and are stored as fat, Benardot said.
The leaner athletes in the study may be giving other athletes--and even nonathletes--a lesson in the value of eating smaller but more frequent meals, Benardot said.
“The idea of three square meals, I have come to believe, is downright wrong,” Benardot said. For instance, the calories consumed at breakfast could be cut in half, with the first half eaten at breakfast and the second half eaten at midmorning, he said. Similarly, half of the calories consumed at lunch could be put off for midafternoon, he said.
The study’s conclusion that metabolic change can create fat buildup does not sit well with a leading researcher in exercise and metabolism, Jack H. Wilmore of Texas A&M; University.
“Something doesn’t seem right here,” Wilmore said. “I am not convinced that energy efficiency really changes that much.”
Nor does the study design, essentially a one-day review of eating habits and exercise, seem compelling to Wilmore. This type of study may come up with interesting leads, but researchers would have to follow the athletes over a much longer period to prove that caloric deficits trigger fat buildup, he said.
However, another researcher supports the concept that athletes who eat lightly during the day but heavily at night inadvertently train themselves to amass fat. Benardot and his colleagues may be onto something, said Melinda Manore of Arizona State University.
As for the study design, changes in caloric deficits during the athletes’ day are hard to track, and the Georgia State researchers’ method “may be as good as you are going to get,” Manore said.
And the findings may lead coaches and athletes into better eating habits, Manore said.
“It may get the coaches to realize you have to get these people to eat,” Manore said. And if athletes realize they can be more successful at avoiding fat by breaking up their meals, this could essentially “give them permission to eat,” she said.
