My brother and I had just finished watching "The Hustler"; we decided to try and play straight pool for 24 hours straight, went to a 24 hour pool hall in Houston (Cornbreads)...we got to 18 hours without a break, had moved to 8 ball at some point during the night, and quit...I was 23 years old, in great shape, and was smoked...I felt numb below the waist, my back was shot and I was seeing things out of the corner of my eye. Never tried it again. I routinely shoot 3 and 4 hour sessions, occasionally will do 8 hour session during tournament play, but it hurts. I will normally run through 40-50 racks of 8 ball or 9 ball on my Diamond at home.