A video from "LADbible" has been doing the rounds recently, showing members of a Russian fitness group performing feats of amazing speed. The video shows several clips of them punching something or someone so quickly that you barely see any movement, punching in circles in front of their body with a speed that makes their arms blur, and repeatedly punching something in front of them at an unbelievable rate.
Each clip has some kind of "evidence" in it to show that it’s not faked - a timer running on a mobile phone, a TV playing at normal speed in the background, or a pendulum swinging, for example.
Of course, despite their assurances to the contrary, these guys are just trying to trick people. This becomes obvious when you replay the video at normal speed and look out for anomalies. For each apparent trick of superhuman speed, there will be telltale signs of video manipulation. So, how are they doing this?
For the single punches that happen too quickly to see, they’re simply removing a bunch of frames from the video when the punch happens. As long as the camera is steady on a tripod, which it always is, removing those frames isn’t very obvious, until you look at other things that are moving in the shot - usually people. People are constantly moving a little when they stand, swaying slightly as they balance on two feet. So when you remove frames from a video, those little movements become a small but obvious instantaneous jump or shift to one side. And as soon as you see that little jump, it becomes obvious that they’ve edited the video.
For the super speedy arms, the trick is slightly different. The shot is recorded at normal speed, and then part way through the video an editing tool is used to split the video in two somewhere between the person performing the trick and the device being used to show that no trickery is being used. From that point on, the part of the video with the person is sped up and it’s hard to see where the join between the two halves is. However, if you look at the person’s body, you’ll see that not only do their fists speed up, but also the way their clothing moves, the movement of their legs, etc all speeds up too. And anything else in frame, like curtains blowing in the wind, will start moving faster. At the end of each clip they slow the video back down, but never show the person going back to the timer - because the two halves of the video are now out of sync, and if they walked across the screen they would disappear when they reached the split between the two halves of the video, and the game would be up.
It’s a clever set of tricks, and I’m not surprised that a social media group such as LADbible who are interested in getting as many views as possible on their videos hasn’t bothered checking for these kinds of clues that they’re fakes before sharing the video to their millions of followers. Just so long as these videos aren’t being used to recruit people to a gym and take people’s money in return for the promise of superhuman abilities, I see it as nothing more than a bit of harmless fun - apart from the occasional person who may try it at home and end up accidentally punching themselves in the chin!