I always believed that fat loss was from energy from the fat cells used up by the body and excreted. What I didn't realize was that excretion was also through exhaled breaths.
This would explain the amount of weight I lost in 2013 while I spent 4 consecutive days moving my place of residence. The boxes I had weren't that heavy but there were a lot of them. Add to it going up stairs, down stairs, into the car trunk, out of the car trunk, in and out of elevators, etc. Each day I felt spent but not overly exhausted. What I do remember well was having to stop at certain points to catch my breath as the effort required to move the boxes took its toll. Over those 4 days, I would say I lost almost 4 pounds!
More information about this phenomena can be found here:
https://ca.shine.yahoo.com/exhaled-pounds-fat-leaves-body-001427049.html
Find any activity that will keep you breathing constantly and intensely, and before you know it, those pounds will come off!
Own it. Do it. Win it!