Respiration of a Four-spotted Skimmer

I was lucky to capture video of a "large" dragonfly on a close-by perch recently. While watching the short video, I noticed the the abdomen expanding/contracting greatly and quickly. Hadn't noticed that extreme of action in the past. So, I did some research on insect respiration and found this excellent website for explanation: HOW DO INSECTS BREATHE? AN OUTLINE OF THE TRACHEAL SYSTEM. Here's the visual: