My impression is that the advice applies more generally than to just physical pain. My impression is that there's a lot of times when your body produces pain-like signals telling you to stop, when it's really in your interest to push through.
And so, to use the emotional example, when I push past fear, I imagine it as weakness leaving my body. I imagine a) becoming a stronger person for having pushed past it and being more capable of pushing past it in the future. And b) I imagine it as weakness leaving the body in the sense of my pushing myself towards an end that is more preferable to me.
when your body produces pain-like signals telling you to stop ... Mental ... Emotional
I think you're confusing your body signaling with pain and your mind yelling "I don't wanna!" These are very different things.
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