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productive, mentally sharp and emotionally balanced and full of energy all day long.
Scientists are still learning about the concept of basal sleep need. Sleep needs are individual. Just like any other characteristics individual is born with. Each person has his or her own biological clock that may respond differently to external stimuli than others. The amount of sleep he needs to function best may be different for an individual than for someone who is of the same age and same gender. Women have the tendency to sleep longer than men. Sick people usually need more rest so their immune system can work better. The quality of sleep often depends on age, health, circadian system, body metabolism, physical work level and gender. Usually, the faster the metabolism, the more sleep needed. Researchers have also found out that there is a strong relationship between the amounts of sleep and body temperature: Tendency to fall asleep rises as body temperature reaches its minimum and vice versa. Therefore, if we go to bed long before our body temperature reaches its minimum, our time asleep could result longer as we are further away from the time when our body temperature starts to rise again. Although the average duration of sleep acts as a good guideline, it does not tell us about the quality of sleep. Extensive data collection reveals that people, who sleep between 6.5 hours and 7.5 hours a night, as they report, live the longest.
How much sleep does one need is a question that has baffled scientists for centuries and the answer is no one is really sure. Some people seem to get along fine with very little sleep (ranging from 1 to 5 hours a night) and lead a productive live, while the others may
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