I'm a retired longhaul trucker, 31 years, over 4,000,000 miles ... over the years, I reached my best efficiency, if I slept about 5 hours a night (or,day) ... after about a week of that, I would need a full night's sleep (8 or 9), then I could comfortably repeat the 5-hour cycle ... I felt great with 5, and sluggish with 8 ... even now, I usually sleep only 5-6 hours per night, and would probably have less, if I weren't 'medicated' :jointsmile: ... truckers talk about sleep schedules a lot, etc., and there's a lot of variance, but we aren't able to change it drastically ... I think we're each individual slaves to our sleep needs ... I gotta go take a nap