How Much Sleep is essential? Age and timings of sleep

HOW MUCH SLEEP?

 Sleep is essential, but the amount required varies. The usual sleeping time for the adult is eight hours, but some people need less, some need more. Everyone has heard the story of Thomas A. Edison sleeping only two hours a night-and the romantic picture of Edison working on through the night to invent the electric light bulb suggests that any of us, strong willed enough, could cut down on sleep and have more time to become famous and rich. The fact is that Edison, though protesting that sleep was a loss of time and opportunity, was concerned about getting his own quota of sleep, according to his own diaries.

He napped often, and frequently drifted back to sleep for another hour or so after waking in the morning. Some physicians are firmly convinced that if shortchanging yourself on sleep does not catch up with you quickly, it will, and there will come the day when you suddenly appear to lose your energy, become prone to ailments, and suffer a general deterioration of health. There is no simple answer to the question of how much sleep is best. The essential test is whether you feel rested in the morning and have enough energy to carry on the day's activities.

Eight hours, as we have noted, is an average figure. If you do very heavy physical work or extremely exacting mental work, you may need more. Children need more sleep than adults since they are growing fast and are very active. Old people often have been thought to need less sleep; this is not necessarily true. They may need more, depending upon their activity and health. It could be a most worthwhile exercise to make your own investigation into your sleep needs, on the simple basis of experimenting to determine how much sleep makes you feel good, how much less makes you feel out of sorts, irritable, fatigued. 

Stages of sleep and good health and research

 It is quite normal now for a sudden body spasm to on, perhaps awakening you for a fraction of a second. And then you move into stage 1 sleep; voltage from your brain is small, changing rapidly pulse is slowing, muscles relax. You enter stage 2 sleep as brain waves rapidly grow larger. If at this point you were to be awakened, you might well believe you had not been, sleep at all, though you have been for about 10 minutes. In about half an hour, you are in stage 3 sleep.

 Brain wave voltage is higher, the waves slower. You are breathing evenly, muscles relaxed, with temperature and blood pressure still falling. It would take a loud noise now to wake you. Soon you move into stage 4 sleep, with large slow brain waves. This is the very deep sleep that most people may think of as real sleep, but it is only a small fraction of the total.

After about 20 minutes of stage 4 sleeps, you start to move upward into lighter sleep. Now you may turn in bed or make some other movement; you are almost at the consciousness level. But instead of waking, your eyes move under closed lids, much as if you were watching a movie. Your heartbeat is now irregular and your blood pressure fluctuates. You are dreaming and if awakened at this point you can describe the dream in detail-but if you are not awakened then, you may or may not remember the dream in the morning. After about 10 minutes of REM or dream sleep, the cycle starts again. 

This, then, is the sleep process. There are still many unknowns. For example, there is no clear answer to the natural question: which sleep is better, deep or light? Nature apparently considers both necessary and oscillates between them. Also, there has long been a theory that sleep is needed in order to allow the body to get rid of "fatigue toxins." The idea is that during an active day, with constant contraction of muscles, certain chemicals are produced which are disposed of as waste.

But during activity the disposal rate is not sufficient to prevent some buildup of the materials and fatigue results. It has been thought, therefore, that as this fatigue linked 10 undisposed wastes builds up, sleep results. Yet, if this were the case, "toxins" should disappear during the night and we should leap out of in a state of exuberance in the morning. But this rarely happens. In .my case, with or without adequate explanations of why, we do adequate sleep is necessary. 

Without it, not only do we feel fatigued; we also feel emotionally drained, which Reed Army Institute of Research in Washington have demonstrated that the longest a person can go without sleep is about 240 hours, or 10 days. And volunteers who went through the experience found it much like torture. Even after 65 hours of sleeplessness, one volunteer was discovered in a washroom, frantically trying to wash "cobwebs" from his face, believing he was covered with them. Sleep is needed for emotional stability as well as physical refreshment.