I, too, have more than enough energy while I'm fasting. Last weekend, some friends and I went hiking in the Rockies near Canmore. When we started, I hadn't eaten in 18 hours. It took 4 and a half hours to get up and down the mountain, due to my friends needing to stop and rest every couple hundred meters. I could have kept going on and on, and didn't even sit down during a number of their stops. I even had more than enough energy to make a mad scramble to the peak.
When we got down off the mountain, I was hungry, but it wasn't uncomfortable. I just knew "it's time to eat." That's how it is all the time. I break the fast from the urge to eat, rather than the pang to eat.
But it helps tremendously to be active. Anything to keep your mind off of food.
You lousy kids! Get off my savannah!