Fitness wearable stats illustrate what you thought: we're less active when it's cold
 

It's hard to fight nature. We mammals have an instinctual urge to hibernate when the mercury starts dropping, and thanks to activity trackers we have some data to prove that theory holds true (if we actually get that sleep is another story). By...

http://www.engadget.com/2014/11/20/w...=rss_truncated