DOSE - the happy chemicals of the brain - Dopamine, Oxytocin, Seratonin, and Endorphins.

Endorphins, in "most" people, are released during or after physical exercise. Upon release, they help reduce pain, which then sometimes triggers dopamine. This combination is called "runner's high", which can be why people choose to continue running. Those that don't ever "feel" this way, may give up on running and find other ways to get physical activity in their life regimen. Those that never physically exercise typically end up with weight problems, but not always.

The way the brain chemistry varies between people can be different based on many factors such as DNA, food, gut bacteria, environmental chemical exposure, and more... Humans, today, share the same set of chemicals empowering their bodies, however there is mostly small, but sometimes larger, variation in the quantities of those chemicals. So, we're all different, and yet we're all the same.

Chemistry plays a big role in perception of an activity - was it a good activity, or a bad one? Good activities tend to reinforce repeat behavior of that activity, bad ones help reinforce memories of what not to do. So, if you've never experienced runner's high, I could understand why you wouldn't be interested in running. Just don't be sedentary - the human body was not [built|evolved] for sedentary life.

... and not to bring AI into this conversation, but its why the tech is so different - its not tied to the materiality of our brain chemistry. Its merely the [approximate?] representation of our own brain electrical activity without the consequence of all that we are - pain, sadness, happiness, bliss, love, etc...

Full disclosure: I received a dopamine release from the writing of this reply ;P