| Swimming done at the same intensity as running will expend 4 times the amount of energy. However, it's a lot harder to keep up the intensity in swimming unless of you course you walk for you cardio.
On another note, the extra calories supposedly burned from fasted state aren't very much more than having eaten...in other words, there's really no benefit. You should target over all calories and not just fat or you're going to be doing a lot of cardio. | 
