I've been thinking a lot about weight lifting over the last few weeks, and it strikes me that there is a zen aspect to the activity. The mental concentration that is required, as well as the physical effort, causes you to sort of fold into yourself. The outside world sort of flickers and dims, and everything focuses on that one set of muscles that you are trying to work.
There is a thing called "the weight lifter's stare" which is analogous to the runner's high. It's a feeling of quiet exhilaration, a quickening of the heart rate, a profusion of sweat, a rushing of blood to the muscles. You find yourself standing and staring, catching your breath, and don't realize when the guy next to you asks: "Are you using those sixties?"
I wouldn't say that my routine has always been as intense as it should be. And there was a lot of time back in the 80's when I did not understand what I was doing. I never had any instruction. I just went in and tried it. I got hurt a few times. Pulled a muscle here and a muscle there. But I've kept at it, and I've found that after almost 29 years of working out that I've come to understand what my body wants and what it can take.