New research challenges the assumption that you can 'work up an appetite. It's commonly assumed that you can “work up an appetite” with a vigorous workout. Turns out that theory may not be completely accurate – at least immediately following exercise.
New research out of BYU shows that 45 minutes of moderate-to-vigorous exercise in the morning actually reduces a person’s motivation for food. Professors James LeCheminant and Michael Larson measured the neural activity of 35 women while they viewed food images, both following a morning of exercise and a morning without exercise. They found their attentional response to the food pictures decreased after the brisk workout.
“This study provides evidence that exercise not only affects energy output, but it also may affect how people respond to food cues,” LeCheminant said, according to the news release, "Overeating learned in infancy, study suggests." The study appears online, ahead of print in the October 2013 issue of the ACSM journal Medicine & Science in Sports & Exercise, measured the food motivation of 18 normal-weight women and 17 clinically obese women over two separate days.
On the first day, each woman briskly walked on a treadmill for 45 minutes and then, within the hour, had their brain waves measured. Electrodes were attached to each participant’s scalp and an EEG machine then measured their neural activity while they looked at 240 images – 120 of plated food meals and 120 of flowers. (Flowers served as a control.)
The same experiment was conducted one week later on the same day of the week and at the same time of the morning, but omitted the exercise. Individuals also recorded their food consumption and physical activity on the experiment days.
The 45-minute exercise bout not only produced lower brain responses to the food images, but also resulted in an increase in total physical activity that day, regardless of body mass index
“We wanted to see if obesity influenced food motivation, but it didn’t,” LeCheminant said in the recent news release, BYU study says exercise may reduce motivation for food. “However, it was clear that the exercise bout was playing a role in their neural responses to the pictures of food.”
Interestingly, the women in the experiment did not eat more food on the exercise day to “make up” for the extra calories they burned in exercise. In fact, they ate approximately the same amount of food on the non-exercise day.
Larson said this is one of the first studies to look specifically at neurologically-determined food motivation in response to exercise and that researchers still need to determine how long the diminished food motivation lasts after exercise and to what extent it persists with consistent, long-term exercise.
"The subject of food motivation and weight loss is so complex," Larson said in the news release. "There are many things that influence eating and exercise is just one element.”
Bliss Hanlon, a former graduate student at BYU, was the lead author on the study and Bruce Bailey, an associate professor of exercise science, was a co-author on the study. You also can check out information on another study, as a recent news release explained in the report, "Overeating learned in infancy, study suggests."
Other information and articles that are helpful include reports on research subjects such as, "Study shows how much extra pounds slow you down," "Study: Pay kids to eat fruits & veggies with school lunch," "Study: Kids teased in P.E. class exercise less a year later," "Whoa there! A quick switch to 'barefoot' shoes can be bad to the bone ," and "Overeating learned in infancy, study suggests."
Psychologists found that kids who got teased during PE were less physically active 12 months later -- whether or not the child is overweight
In a new study published in the Journal of Pediatric Psychology, researchers found that anti-bullying efforts may boost physical fitness, according to a January 16, 2014 news release, "Kids teased in PE class exercise less a year later."
The study found that children who were bullied during P.E. class or other physical activities were less likely to participate in physical activity one year later. Overweight or obese children who experienced teasing during physical activity had a lower perceived health-related quality of life (referring to physical, social, academic and emotional functioning) one year later.
Even children with a healthy weight who were bullied during physical activity tended to exercise less often one year later
Many previous studies have already correlated bullying with decreased physical activity among kids who are obese or overweight, but it was surprising to find that the correlation didn’t end there.
“Our finding that this applies to normal-weight kids also was novel,” said Chad Jensen, according to the January 16, 2014 news release." Jensen is a psychology professor at Brigham Young University (BYU) and lead author on the study published in the Journal of Pediatric Psychology.
This study looked at associations between bullying, physical activity and quality of life over time, following up with the same participants after a full year
The participants in this study were 4th and 5th grade students from six different elementary schools in the Midwest. Participants completed three surveys at the beginning of the study and then completed the same three surveys again one year later.
The first survey asked questions about problems with health and activities, emotional well-being, getting along with classmates and academic abilities. The second survey assessed teasing experiences during physical activity. The third survey asked specific situational questions to determine whether the student had been bullied during physical activity and the emotional effect it had. The questions explored experiences such as:
- Being made fun of when playing sports or exercising.
- Not being chosen to be on a sports team or other children looking or acting upset when the child was placed on the team.
- Being called insulting names when playing sports or exercising.
Study results showed a decrease in physical activity of healthy-weight students who are bullied, and a decrease in health-related quality of life for students who were overweight or obese who reported teasing in the first survey
“Overweight kids who were teased reported poorer functional ability across domains (physical, social, academic and physical),” said Jensen, according to the news release. “If we can help them to have a better perception of their physical and social skills, then physical activity may increase and health-related quality is likely to improve.”
Whereas most schools participate in comprehensive anti-bullying programs, Jensen recommends implementing policies that discourage peer victimization based on physical abilities. “We hope our study will raise awareness that educators should consider bullying prevention during physical education and free play (recess) when kids may be discouraged from being physically active because of teasing experiences,” Jensen said in the news release.
You may wish to explore other articles such as the BYU study that says exercise may reduce motivation for food. See the recent news release, "BYU study says exercise may reduce motivation for food." Or check out the article, "Guilty parents rejoice: study finds some active video games qualify as exercise."