I usually always run outside on the hard pavement, but once I went in the hotel exercise room to run on the treadmill, I could have went another hour at least, but I stopped at an hour because I wanted to see some sports and eat. My point is treadmill is a break from pavement, and you burn more calories since you can go much longer, I wish I had my own.
BTW what is the longest time anyone has ran?
Mine was one hour and thirty minutes for ten miles, if you do the math that ain't fast, but that was one of the first runs they made us do for cross country practice.
Do we have any marathon runners here?