As far as I know, they tend to strengthen inferior and superior rectus muscles which are weak in 180 astigmatism.
But, it seems that up-down movement isn’t that effective because I quite don’t feel muscle stretching. And as a person who knows good EOM anatomy and actions, must to say that up-down movement also strengthens inferior and superior oblique muscles which have no relationship to astigmatism. It’s a unwanted side effect.
I also found the next exercises:
- center and down-in, center and up-in
- convergence from downgaze and upgaze
But these two also strengthen medial rectus muscle and it’s risky for me as I have medial rectus overaction.