Doesn’t the Navy regularly drug test?
And, presumably you’re intelligent enough to know that alcohol kills brain cells-(not just damages but KILLS)?
No amount of exercise can restore dead brain cells. Granted, you have a ton of them but once they’re gone they’re gone. And you never know when you might end up needing them so that your brain doesn’t turn to pudding in old age :)
Until you specify WHICH drugs you’re referring to, it’s an impossible Q to answer.