The body's physiological stress response, including epinephrine release, is the same regardless of the stressor (e.g., challenging workout, hot coal, lion).

“Your body does not know the difference. It has a primordial kind of physiological response that it's created over millions and millions of years. And I think that that physiology is not changing. And it's fixed in a particular way right now, that it doesn't understand the difference between whether it's six by 10 doing a challenging workout over here, whether it's putting my hands on the hot coal, whether there's a lion stood in front of me or whatever, that epinephrin response from the level of the brain down to the whole signaling cascade is the same.”