Humans living alone typically have lots of other social contact -- at work, shopping, on the phone, social outings.

It's important to emphasize that this work is not directly relevant to humans. First, rats have a universal drive to run. While some people may feel internally motivated to exercise, most do not and need additional incentives.

Stress hormones go up in runners and yet, under certain circumstances, these hormones don't affect the brain in a negative way.

That said, our study adds to the existing literature that positive social interactions can buffer the effects of stress on the body and brain.

This reinforces the idea that social support helps to lessen the negative consequences of stress.

Our experience with her has been wonderful. She's really a pleasure to work with. She's really a well respected model.