I think the core of „just try to physically do something“ sometimes is to believe in your own abilities that you could theoretically definitely do it at all.
This is about motivational quotes saying you should at least try things [example: „try and fail, but never fail to try!“] and that it‘s hard to really just simply do it.
I have come to the conclusion that every external process is driven by internal forces and rooting from internal beliefs. Because when you allow yourself to believe in your capability, it is so rewarding that the question is not wether you try „it“ or not, it‘s just „would I like to take part in this experience with myself, yes or no?“ And if the answer is yes, you don‘t have to force yourself into trying, it happens naturally and doesn’t cost you any „self-discipline-energy“.