Ok what I think is the biggest problem though is with IF we are supposed to be tapping into stored glycogen throughout the day. By having the bodies insulin low and glycogen higher pulling fat from the body to be used as fuel we get higher fat metabolism all day while fasting. What might be happening is working out in the am you are burning up all of your glycogen stores and getting lower blood sugar than the body can turn over to a fat metabolism.

When are you fasting? Breaking the fast? It takes a special breed to work out hard and not eat for 16 hours. I think we either need to work on your workout schedule, timing of your fast or maybe even try using some BCAA's to fuel the workout and the times between your workout and first meal.