There also seems to be something about sitting itself that is bad for one's health. Studies in both animals and humans have found that sitting leads to changes in resting glucose levels and blood pressure, and that lots of sitting bumps up levels of certain biomarkers of cardiovascular disease and cancer.
"The take-home message is clear: we may not know exactly why sitting is bad for you, but if you reduce the amount of time spent sitting, there are real health benefits," Patel said.
Researchers say the overall message is to move beyond thinking about physical activity as something you do once a day for half an hour. That suggestion has enormous implications for how people currently work, commute and spend their free time.
Katzmarzyk said since many people spend at least eight hours each day sitting at a computer, the workplace is an ideal place to start looking for ways to reform behavior. Patel said changes don't have to be major -- people can get up to talk to colleagues instead of emailing them, or spend a few minutes of their lunch breaks taking a short walk.
And of course, a good place to start making changes is by squeezing the recommended 30 minutes of exercise into every day.
"We have to get folks to understand that doing anything is better than doing nothing," Patel said.