Just to add a little bit more, the best I’ve come to manually reproducing this effect on my own is through long bouts of exercise. Maybe it’s the same effect as the “runner’s high”. I used to be a firefighter and I’d experience a similar effect when I would spend all day outside doing PT (physical training). Come 5 o’clock, after 8 hours of exercise, everyone would be dying, and I’d be experiencing a euphoric boost of energy, and I’d help all the instructors clean up the training grounds. Whenever I’d stop, I would crash, hard. It’s possible for me to feel this feeling through exercise, it’s just impractical to devote 8 hours a day to exercise in order for me to feel it.