Exercise lies in the brain - study

It is the equivalent of two hours of strenuous exercise, such as running or swimming, 3.5 hours of moderate exercise, or six hours of light exercise, say the scientists.

It is the equivalent of two hours of strenuous exercise, such as running or swimming, 3.5 hours of moderate exercise, or six hours of light exercise, say the scientists.

Published Sep 4, 2014

Share

London - Ever struggle to stay motivated when planning a trip to the gym? Well, it may not be your fault – it may all be down to the way your brain’s wired.

Scientists have pinpointed the region of the brain that is responsible for exercise motivation.

While the finding could one day lead to a way of encouraging people to be fit and healthy, researchers say it could also be used to create better treatments for depression.

Eric Turner and Yun-Wei Hsu, of Seattle Children’s Research Institute’s Centre for Integrative Brain Research, discovered that the dorsal medial habenula controls the desire to exercise in mice.

The structure of the habenula is similar in humans and rodents and these basic functions in mood regulation and motivation are likely to be the same across species, they said.

The knowledge that such a specific area of the brain may be responsible for motivation to exercise could help researchers develop more targeted, effective treatments for depression.

Exercise is known to be the most effective non-pharmaceutical therapy for melancholy.

Changes in physical activity and the inability to enjoy rewarding or pleasurable experiences are two hallmarks of major depression, Turner said.

“But, the brain pathways responsible for exercise motivation have not been well understood.

“Now, we can seek ways to manipulate activity within this specific area of the brain without impacting the rest of the brain’s activity,” he said.

The research, published in the Journal of Neuroscience, used mice that were genetically engineered to block signals from the dorsal medial habenula.

Turner’s team collaborated with experts at the University of Washington to show that the genetically engineered mice were lethargic and ran far less than typical mice, which love to run in their exercise wheels. The genetically engineered mice also lost their preference for drinking sugary water.

“Without a functioning dorsal medial habenula, the mice became couch potatoes,” Turner said.

“They were physically capable of running, but appeared unmotivated to do it.”

In another group of mice, the team activated the dorsal medial habenula using laser technology called optogenetics.

The mice could choose to activate this area of the brain by turning one of two wheels with their paws.

The scientists found that the mice “strongly preferred” turning the wheel that stimulated the dorsal medial habenula, which they say demonstrate that this area is linked to rewarding behaviour. – Daily Mail

 

What is the dorsal medial habenula?

The dorsal medial habenula is a tiny area of the brain that has been found to control the desire to exercise in mice.

 

A study in 2010 revealed that the habenula plays a key role in helping animals survive in a world full of hidden rewards and dangers. It inhibits dopamine-releasing neurons when an animal fails to obtain a reward and is involved in responses to pain, stress, anxiety, sleep and reward.

Related Topics: