the cleanest and best workouts are going to be when you train with 0 sugar, 0 stims, 0 food, maybe a few sips of water that is it.
when you get used to training with sugar like this you train your body to require it. hope that makes sense
having said that for PURE powerlifters its good to have a banana and maybe an egg or two about an hour before you train, but make sure you evacuate pre gym
as far as bubble gum, I would NEVER consume refined sugar going forward. its already in everything and you get too much of it as it is. adding more is beyond crazy. remember sugar is a magnet to disease