The lighting is much different for the Arnold Classic night show than it is for prejudging. Completely different. For prejudging, your are being compared to each other, and you need to complete package - to edge the competitor.
During the evening show, you are doing your posing routine, and enjoying yourself more. Many competitors eat a lot of carbs, protein and bulk up, gaining weight (although some can lose weight), and thus, appear fuller and more vibrant on stage.
I know a number of competitors did just that between prejudging and the finals.
