we lit them by flash as you can see, and flash is very fast, so they are frozen. It will happen regardless of shutter speed, as the rest of exposure is in dark room. One can do even such things: [link]
"You know what my days used to be like? I just tested. Nobody murdered me. Or put me in a potato. Or fed me to birds. I had a pretty good life. And then you showed up. You dangerous, mute lunatic. So you know what? You win. Just go."