Actually most digital camera have a load time when you take a picture. This looks like a fireman has walked out of the frame but his bright yellow
overalls and reflector tape remained. So in my opinion those are not white sneaker but the reflective bank around the fireman's pant leg.
Looks like a time exposure that someone ran through. The shoes spend the longest amount of time in one place so they get the most exposure. The upper
body is in constant motion so makes very little or no impression, especially if the person was wearing dark clothes.
I've done a lot of time exposures and that's what it looks like to me.
Yeah that really doen't look like long exposure to me.
I have experienced long exposure and each time the object has moved quickly, if it was someone, then they would have to be running but it doesn't
look like someone running does it!