If you get some uselessly vague advice like "don't eat/do things like <list of hyperspecific examples and nothing else>", keep talking and asking (and mentioning your understanding so far out loud repeatedly, even if it's probably wrong!) until they tell you the underlying mechanism.

Example:
"Avoid intensive exercise."
"Okay, what qualifies as 'intensive'?"
"Well, try to avoid sports like football or tennis, for example."
"Okay, but what about VR then? It's virtual so you can't get hit by anything, but I don't know if that's safe enough."
"Ah, well, you should avoid any kind of exercise that causes shocks to your body, like when jumping a lot."

And just like that, you learn the underlying mechanism that the advice originates from (which might be "shocks to your body can cause issues with healing" like in this case), and now you can reason for yourself about whether something is or isn't safe to do, instead of being limited to a (usually heavily neurotypical) set of 'common' things.

(Sometimes you can also just ask point blank what the underlying mechanism is, but it's pretty much luck of the draw whether you get a doctor who trusts you enough to actually engage with that.)