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Medical Is 8 hours sleeping is a myth?

  1. Nov 2, 2008 #1
    i wanted to know the fact really in this scientifical issue..how much of sleeping a body should have?..we been told many times that the 'healthy sleeping' should be 8 hours, but from few days a friend of me told me thata german surgery found 2 hours only are sufficent for the human body..can anybody please explain this to me?

    thanks in advance
  2. jcsd
  3. Nov 2, 2008 #2
    it's not a myth for me personally. i think sleep deprivation is mostly a way to dehumanize political prisoners and medical students. ;)
  4. Nov 2, 2008 #3

    Gib Z

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    Sufficient to continually survive, or to operate at a decent capacity lol? My dad said ages ago that 8 hours is approximately an optimum level, though it varies between about 7 hours for young adults and quite a large number for babies. Something like that.

    Im pretty sure 2 hours is not enough for true optimum capacity, but its enough to falsely feel "refreshed" because once you've slept for about 1.5 hours you've reached REM, which is the deep sleep part. If you reach that for a bit, your brain thinks its gotten a lot of rest, even though it hasn't.

    Dodgy explanation and I'm probably wrong, but thats what I remember.
  5. Nov 2, 2008 #4
    Approximately eight hours of good sleep is required by most adults for optimal performance during waking hours. Teenagers generally require about nine hours. The effects of sleep deficit are seen in both the cognitive and physical realms. You can find a good starting point for learning about this by Googling "NIH sleep".
  6. Nov 2, 2008 #5


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    Some empirical (if antecdotal) results:

    Personally, my waking performance is very closely tied to how close I get to 8 hours of sleep the night before. If I only get 7 hours, I get drowsy at my desk. Quite consistent.
  7. Nov 2, 2008 #6
    Now this is some interesting news as i read a self help book where the author claimed only 6 hours were necessary. I tried to do that <i usually have to during stressful times at university> but i always found the need to have little naps during the day for abt 20-30 mins.

    So in the end i dropped that practice.
  8. Nov 3, 2008 #7
    Yes, but what really tease me about this, is how do some ppl sleep in the range of 4-5 hours and they are doing well on the congitive and physical realm! i think it depends on your physical daily action ..i think that what's all about..i read in the biography of T.Edison that he was able to sleep only 2 hours daily or performs intermittent sleep, how's the hell is that?!!

    from few days i tested my concentrating and congitive rate , i slept about 4 hours or maybe 3 hours in a day and i went to my lectures i was quite sleepy in the first lecture (mind action) but when i started using the computer in the middle of the day i was rate of concentration was very well (physical action), then i tried to do the same day after day but i found that it's IMPOSSIBLE to obtain a continues constant sleeping rate and you should equalise the sleeping hours in your body one way or another..but i still not sure about this.
  9. Nov 3, 2008 #8
    Some people are able to function on very little sleep. In fact, if you are willing to take enough modafinil, you can probably go without any sleep at all; of course, you'll run the risk of becoming situationally insane and dying of a stroke within a few months. During the Viet-Nam war, the Army provided large amounts of speed to LuRPs so that they could go on week-long patrols with perhaps an hour's sleep a day. It wreaked havoc on their minds and bodies.

    I suggest you go to the NIH site and look at the extensive research they have documented for sleep deprivation. Good science always trumps anecdotes.
  10. Nov 3, 2008 #9

    jim mcnamara

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    Normally, it is better to discuss real research.
    This page has a lot of PDF's on the topic of sleep deprivation and performance:
    http://www.spokane.wsu.edu/researchoutreach/Sleep/research.asp [Broken]

    This one:
    Belenky G, Wesensten NJ, Thorne DR, Thomas ML, Sing HC, Redmond DP, Russo MB, Balkin TJ (2003). Patterns of performance degradation and restoration during sleep restriction and subsequent recovery: a sleep dose-response study. Journal of Sleep Research 12: 1-12

    Finds that people restricted to regimes of 3,5,7 hours of sleep per night all showed varyling levels of decreased performance on tests designed to measure motor skills and attention. Less sleep == more degradation. Another group, where sleep was restricted to 9 hours showed no degradation at all compared to baseline.

    I dunno about exactly 8 hours of sleep, but there probably is a point somewhere between seven and nine hours of sleep that is the break-even point - any less shows performance degradation, any more keeps baseline performance.

    So I would say '8 hours of sleep is probably a good starting point for assessing your need for sleep'.
    Last edited by a moderator: May 3, 2017
  11. Nov 3, 2008 #10
    Thanks indeed for all who replied me!.. TVP45, thank you ill look deeply in NIH site, iam not sure modafinil would be my best choice :))
    ,..and jim thanks really for the webiste thats a very useful dose :))
  12. Nov 5, 2008 #11
    So many people, so many responses. Lets say I'm in the fire brigade on 24 hrs shifts incidententily, being allowed 3 hrs of sleep in that period. Ten what? You'd do a normal day off after that sleeping 7 to 8 hours to recover in the next few days, before another 24 hrs shift.

    And that's no problem whatsoever, meaning that it's hard to say for any individual which sleep/wake scheduke they can adhere to.
  13. Nov 5, 2008 #12
    LOl, u mean working as a electrical capacitor, charging and discharging lol, i dont think that would suit me really , after while you will be alarmed by disturbance in your inner biological sleeping system..and u will have ure head giddy most of the times which means some lost in ure normal rational congitive, but that actully what your body genes do in spite of yourself without a real controll of yourself i just want to know is it impossible to have a constant continuous sleeping rate (*with keeping a rational congitive and well efficency rate during your day*)??..i think it is

    and thanks for sharing me :)
  14. Nov 7, 2008 #13
    I've read that lack of sleep can cause obesity. During sleep the metabolic rate slows down. The metabolic rate during sleep is regulated so that the energy reserves you have when you wake up is the same as it was the previous day.

    So, if you have used more energy and eaten less than average, the metabolic rate during sleep will be a bit slower, while if you haven't used a the usual amount of energy and eaten a bit more than average, the metabolic rate during sleep will be higher.

    This mechanism allows animals in the wild to have a stable body weight. Without this mechanism, an animal that has to expend a little more energy to find the same or slightly less amounts of food than usual would eventually starve to death.
  15. Nov 7, 2008 #14

    The effects and benefits of modafinil are vastly overrated.
  16. Nov 7, 2008 #15


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    I have worked extreme shift schedules, including the "southern swing" and rotating "12-on-12-off" schedules in physically demanding industrial settings. There is no substitute for sleep, and if your schedule is designed to "jet-lag" you, even getting 8 hours of sleep regularly can leave you deprived.

    For those of you who have not worked the "southern swing" shift schedule in a physically demanding industrial setting, I can personally attest that it will take many years off your life. I think that paper companies forced people into these schedules so that by the time they might be eligible to retire, they would die.
  17. Nov 7, 2008 #16
  18. Nov 8, 2008 #17
    There were times I didn't sleep, then what ? I am still here WELL,
    By days, I am getting older and I am also having hard time to keep thinking about a particular event, I forget more often anything past. Then I think we all get older.
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