Physical activity reorganizes the brain so that its response
to stress is reduced and anxiety is less likely to interfere with normal brain
function, according to a research team based at Princeton University.
The researchers report in the Journal of Neuroscience that
when mice allowed to exercise regularly experienced a stressor — exposure to
cold water — their brains exhibited a spike in the activity of neurons that
shut off excitement in the ventral hippocampus, a brain region shown to
regulate anxiety.