Published October 29, 2014
Individuals make choices every day that relate to eating and physical activity. New research findings indicate that motivation to eat, or the reinforcing value of food, may be influenced by a number of factors, including physical activity. The study by researchers at the University at Buffalo’s School of Public Health and Health Professions appeared in the in the online edition of the Appetite Journal.
The purpose of the study was to test the hypothesis that short-term moderate-vigorous intensity aerobic exercise would alter the reinforcing value of high (HED) and low (LED) energy density foods in inactive adults. The reinforcing value of HED and LED food was measured at baseline and again after two weeks of aerobic exercise.
“Most of the previous work on caffeine and physical activity had been done in trained athletes, but we were interested in studying sedentary adults in order to better represent the general population,” stated Jennifer Temple, PhD, associate professor in the Department of Exercise and Nutrition Sciences and Community Health and Health Behavior.
In the first study, 41 participants were randomized to a no exercise condition or aerobic exercise for three days per week for two weeks. Then, in a second, follow-up study, 76 participants were randomized to one of four aerobic exercise frequencies, zero, one, three, or five days per week for two weeks. In both experiments, exercise reduced the reinforcing value of HED food compared to baseline and to non-exercise controls.
In experiment two, the five day group also showed a significant increase in the reinforcing value of LED food compared to baseline and other exercise frequencies. Liking of HED and LED foods and consumption of HED food were not affected by exercise treatment. Finally, in experiment two, the five day group reported consuming more energy outside of the laboratory than the other groups. Taken together, these data suggest, in inactive individuals, motivation to obtain HED and LED foods can be altered with a short-term moderate-vigorous intensity exercise intervention. Further research is needed to understand the cognitive and physiological processes involved in food choices paired with exercise.
The study’s participants were ethnically diverse male and female individuals ranging from 18 to 50 years-of-age in Buffalo, NY. Participants were excluded if they were current smokers or had been smokers within the past six months, were currently dieting or had an eating disorder, had any medical conditions or medications which affect appetite or restrict physical activity, did not like any of the study foods being used or if they reported engaging in moderate to vigorous physical activity for greater than 30 minutes more than twice a week.
The study’s lead author is Leah Panek, a graduate student in the department of exercise and nutrition science in the University at Buffalo’s School of Public Health and Health Professions. Co-authors of the study include Kelly R. Jones and Jennifer Temple, PhD.