Do injuries make astral projection harder?

Just recently decided to give this a good try. First attempt last night and I got some black and white visuals before returning to immediate thoughts.

From reading here I can see that “letting go” is a crucial step, I am curious if this step is more difficult more people recovering from injuries or with neurological tightness. I have some disc issues and injuries to major joint structures, and generally have a hard time completely relaxing

Will this make projection impossible, or simply require more powerful skills in meditation?