Exercise reduces anxiety and depression

July 14, 2010

Exercise can ameliorate anxiety and depression-like behaviors induced by an adverse early-life environment by altering the chemistry of the hippocampus, the part of the brain that regulates stress responses, researchers from the University of New South Wales (UNSW) have found.

In the study, rats were divided into groups and either isolated from their mothers for controlled periods of time to induce stress or given normal maternal contact. Half were given access to a running wheel. In addition to being more anxious, animals that were subjected to stress early in life had higher levels of stress hormones and fewer steroid receptors in the part of the brain controlling behaviour.

“Both the anxious behaviour and the levels of hormones in these rats were reversed with access to the exercise wheel,” said UNSW Professor of Pharmacology Margaret Morris.

“We know that exercise can elevate mood, but here we are seeing chemical changes that may underpin this improvement. One of these is increases in brain-derived neurotrophic factor (BDNF), which helps nerve cells grow.

“Many neurological diseases appear to have their origins early in life. Stress hormones affect the way nerve cells grow in the brain. This discovery may be giving us a clue about a different way to tackle a range of conditions that affect mood and behaviour,” she said.

More info: University of New South Wales news