I'm working on animating a salmon and a newb at it. That said, I've watched several tutorials and followed all different methods that are pretty much the same. I built the model with clean topology and worked on several versions.
I did as low poly as I could with the latest version of r20.
When I go to select 'animate' after binding the dynamics of the body just droops from the head and folds the topology on itself. I'm attaching a link for anyone who has advice.