Summary: Exercise appears to increase the brain’s response to food cues, a new study reports.
Researchers have found that running increases the reactivity of certain brain regions associated with attention, reward anticipation, and memory. These changes occurred independently of general changes in cerebral blood flow.
This new understanding may further our understanding of the complex relationship between physical activity, appetite, and food intake.
- Running increases the response to food cues without altering brain blood flow.
- After exercising, the participants reported that their brains responded with higher food signals, but they also felt less hungry.
- This research may expand our understanding of how exercise affects appetite and food intake, providing strategies for managing unhealthy weight gain.
Source: Loughborough University
A single bout of exercise increases responsiveness to food cues in parts of the brain associated with attention, reward anticipation and memory, according to a study A map of the human brain.
Researchers from the UK’s Loughborough University, the University of Bristol, the University of Nottingham and the University of Leicester and Japan’s Waseda University investigated the effect of running on blood flow in the brain and how this brain activity is related to appetite.
They found that changes in the way participants responded to visual food cues occurred independently of changes in overall blood flow in the brain.
The amount we eat affects the systems in the brain and the changes that occur in our body and the food environment we are in.
Previous studies have shown that single bouts of exercise, such as running, can temporarily suppress appetite. However, we don’t fully understand how much exercise affects our ability to eat.
A food signal response is the body’s way of responding to food. It is our response (physically or psychologically) to a sight or smell, for example. Food signal response influences our appetite and how much we eat.
The research team wanted to investigate whether exercise-induced changes in blood flow in the brain could influence how people respond to food. These changes can be captured using functional magnetic resonance imaging (fMRI). An fMRI scan can help us assess what’s going on in the brain by detecting subtle changes in blood flow.
For this study, twenty-three men underwent fMRI scans before and after 60 minutes of running or resting. During the test, they were asked to look at three types of pictures, ranging from low-energy-dense foods such as fruits and vegetables to high-energy-dense foods such as chocolate and furniture.
Researchers found that exercise inhibited how hungry participants felt, but activated several parts of their brains to respond to food cues. Using a different type of fMRI, he observed changes in blood flow in the brain after exercise, although these changes did not appear to affect food cue responses.
Dr Alice Thackeray, Senior Research Associate in Exercise Metabolism from Loughborough School of Sport, Exercise and Health Sciences (SSEHS) was lead author of the study.
She said: “Our findings confirm that individuals experience hunger during and immediately after exercise and provide some insight into the short-term effects of exercise on the brain’s appetite responses.
“While more research is needed to determine the implications of these findings, we do know that the brain plays an important role in regulating appetite and food intake.
“This research is part of an exciting collaboration that we plan to develop further as we continue to consider how exercise and appetite interact, including their effects on central (brain) responses.”
David Stensel, Professor of Exercise Metabolism at SSEHS, added: “The role of exercise in modulating appetite and controlling weight continues to be a hot topic. This research shows that how our brain responds to food cues can be changed by exercise.
“The study provides a springboard for further work to accurately and comprehensively identify appetite responses to exercise. This will give us a better understanding of the role of exercise in preventing and controlling unhealthy body weight gain.”
Dr Elanor Hinton, from the University of Bristol, said: “This research started as a small pilot collaboration between two NIHR BRCs in Loughborough and Bristol. We are pleased that our initial plans to produce this publication have progressed A map of the human brainWhere we shared our knowledge
“Further publication is now pending from this fruitful collaboration, demonstrating the benefits of collaboration within our research groups.”
So exercise and neuroscience research news
Author: Judy Wing
Source: Loughborough University
Contact: Judy Wing – Loughborough University
Image: Image credited to Neuroscience News.
Preliminary study: Open Access.
“Exploring the acute effects of running on cerebral blood flow and food signal response in healthy young men using functional magnetic resonance imaging.” by Alice E. Takray et al A map of the human brain
Exploring the acute effects of running on cerebral blood flow and food signal response in healthy young men using functional magnetic resonance imaging.
Acute exercise suppresses appetite and alters appetite response, but the extent to which exercise-induced changes in cerebral blood flow (CBF) affect blood-oxygen-dependent (BOLD) appetite-related parameters is unknown.
This study investigated the effects of acute running on visual feed-response responses and whether such responses influence CBF dynamics. Randomized crossover design, 23 men (mean ± SD: 24 ± 4 years, 22.9 ± 2.1 kg / m).2) completed fMRI scans before and after 60 min of running (68% ± 3% maximal oxygen uptake) or rest (control).
A five-minute pseudo-continuous arterial spin signal fMRI scan was performed for CBF assessment after exercise/rest with four consecutive repeat acquisitions. BOLD-fMRI was obtained before food-cue response activity and 28 min after exercise/rest.
Food-cue response analysis was performed with and without CBF adjustment. Appetite ratings were assessed before, during, and after exercise/rest.
Exercise CBF was higher in gray matter, posterior insula, and amygdala/hippocampus region, and lower in medial orbitofrontal cortex and dorsal striatum than controls (main outcome test). Page≤ .018). No time-by-trial interactions were found for CBF (Page≥ .087).
Reduces appetite levels leading to moderate to large physical activity (Cohen d= 0.53-0.84; Page≤ .024) and increased food-cue reactivity in the paracingulate gyrus, hippocampus, precuneus cortex, frontal pole and posterior cingulate gyrus. Accounting for CBF variability did not significantly alter the detection of exercise-induced BOLD signal changes.
Acute running evoked non-time-dependent general changes in CBF and increased food cue responding in regions involved in attention, reward anticipation, and episodic memory independent of CBF.