There are thousands of instructional workout videos on YouTube.  But there's only one we know of where you see someone drop weight THIS fast.  

A new video from a fitness website called TheDailyHIIT.com MOSTLY shows a ridiculously in-shape woman doing some kind of crazy workout. 

But at two points in the video, you can distinctly see a bathroom with its door open in the background . . . and there's a guy sitting on the toilet.  (You can see him at :20 and :33.)