1. f. Situación, preparada de antemano, en que se coloca a alguien para obligarle a que haga algo contra su voluntad.
4. f. En algunos exámenes, oposiciones, etc., ejercicio que consiste en la preparación, durante un tiempo determinado y en un lugar aislado, de un tema que luego habrá de exponerse ante el tribunal.
6. f. Taurom. Lidia de toros en privado.
The "encerrona" is an exercise you might try. Basically, it means a "shutting in." Definition 4 is the most relevant definition but I like 1 and 6 as well. [ A situation prepared before hand in which someone is placed in a position to do something againt their will; a private bullfight.]
"In exams, competitions, etc... the exercise of preparing, during a predetermined time and in an isolated place, a theme that then must be presented to the judges."
So the idea is to lock yourself in where nobody else can reach you and just write as much of your project as though you were taking an exam on it. No internet, no books, just yourself and a computer or pen and pad, for 3 hours. This is a jump start method most appropriate for the beginning of a project. You can also do it all day, with breaks. If you have the luxury of an encerrona of a week, that would be great. Most of us have families and other obligations that prevent that.