Best Answer
Fitbit Product Experts Alumni are retired members of the Fitbit Product Expert Program. Learn more
Your Surge will happily track exercises such as running on its own and will calculate the calories correctly. In fact, to get accurate calories, you only need to manually log an activity if you forget to wear your Surge. There's more information on this in this article:
http://help.fitbit.com/articles/en_US/Help_article/How-do-I-log-or-record-an-activity/