What stretching actually does to your body ft. Sofie Dossi

I was a bit disappointed that this video spent so much time on contortionism and completely neglected PNF stretching and how it works. Neglected dynamic and ballistic stretching too. How they differ and their pros/cons would have been much more educational. Especially for a "physics" channel, I'd have expected more mechanical explanations. 

The generic biological and mechanical information was helpful though, esp the graphic design. 👍