Rather watch TV than bike 50 miles? The thought of a hike sound like torture instead of fun? Well, according to two recent research papers you can stop berating yourself for being a couch potato (maybe). Researchers have identified 23 gene locations that control the activity levels of mice. “Can you be born a couch potato? In exercise physiology, we didn't used to think so, but now I would say most definitely you can," says J. Timothy Lightfoot, lead researcher on the project at the University of North Carolina.

No two fads are growing faster than getting fit and going green. Is it possible that by achieving the former, one could also accomplish the latter? Harnessing human movement has long been a holy grail of renewable energy, but real-life implementations have been relegated to advertising stunts and commercially impractical gadgets. But ReRev.com, a startup company from St. Petersburg, Florida, thinks its technology can let us improve our own health, and that of our planet, by working up a sweat.

When I went from footloose freelancer to sessile nine-to-fiver in a huge building, I made a rule: unless an open elevator was waiting, always take the stairs. This is because I knew it was the healthy thing to do.

Go figure—Im right, says a new JAMA study. But not only does the research show that taking fewer steps is unhealthy, it can actually cause disease.