Same. 5 to 6 hours and I feel fine, unless I'm ill or already sleep deprived. I can function on 3-4 hours per night for extended periods of time before I start

Same. 5 to 6 hours and I feel fine, unless I'm ill or already sleep deprived. I can function on 3-4 hours per night for extended periods of time before I start to notice serious deterioration in mental faculties. I believe it's genetic. Some studies have tentatively tied naturally short sleep cycles to a gene variant (http://www.sleepeducation.org/sleep-disorders-by-category/insomnias/short-sleeper http://www.sleepeducation.org/sleep-disorders-by-category/in...). Also, my father sleeps for about the same amount of time as well.