There's no question that regular exercise is essential to health. For the vast majority of our evolutionary history, we've had to exert ourselves -- often quite strenuously -- to get food, find shelter and simply survive.

Over the past century there has been a dramatic increase in the incidence of depression, sleep disorders and obesity. New data suggest that at least part of this increase could be due to the ever-growing exposure to light at night.

If I had a buck for every time I was asked this question, I'd be a rich man. It's a great question, and helps frame a conversation about what it means to be fit.

While some progress has been made to reduce tobacco use and alcohol consumption and to promote healthier eating habits, the lack of regular physical activity has not yet been widely recognized as a standalone health threat.

Many of us know, yet few are willing to admit, that sitting, being sedentary, and living a computer-bound life lead to early death. These facts are so startling, yet there are still so many struggling with adopting an active lifestyle.

Does your kid feel left out? That social isolation may affect more than his or her mental health -- it could also increase obesity risk. That's t...

Whether you are a fighter pilot or a "desk jockey," sitting all day is very hard on the body, even with fancy or expensive chairs. Sitting contributes to collapsed posture and low energy levels -- conditions that are far too common today.

Sharon Gavin used to spend all day on her feet. Now she has a full-time desk job -- and the transition has been a painful one. In 2002, after 12 ye...

You send your kids to day care with the hopes that your preschooler will learn socialization skills. But a new study shows that toddlers in home-based day care may watch up to two hours of TV during their day