Jenny Mace switches from crawling underneath the electrified rails on her way back to the hopscotch course, to climbing between the rails with her head pointed the other direction. This provides a) more challenge, and b) a spectacular view of her ass. And, in case that wasn't enough, we add heavy metal clamps on her nipples (with some really cute moments of Tony attaching the clamps).
I used an iPhone as a bonus camera running at 120fps, and put a single pass through the hopscotch course in super-clean slow motion at the end of the video; the bouncing is great, and don't miss the micro-expressions with each jolt.