Sleep duration.

 Which exercises are shortening a time to sleep, wihout a health harmful.

Such exercises are not having, and to lengthen day for a sleep calculation is not good, thus a systematically sleep lack is negativity affecting on a head brain activity and causing high tirednrss, irritability.

 As by experiments in volunteers tried shortened sleep time,that are healthy peoples are felt bad, lowered work capacity. On the middle for human need are 7-8 hours for sleep night. And a full sleep is feeling energy, good, with good attention, and work capacity staying. But a same norm for all is not having, that for feeling better one peoples having 5-6 hours enough for sleep, with a not extremal conditions, rational, right day regime,every human rely on wisdom of an own organism, that he self - defines a time for sleep need.

 Sleep duration depending from age, emotional condition, your feeling. On emotional high time, and work creative , a few peoples sleep less, and its not affecting on theirs feeling, and not harmful for health. They are waking up ,that good slept and ready to active work.

But on stress situation, conflict, in a sleep needing is increasing, if lack of sleep its a bad on nerve system activity, systematicaly sleep lack is a risk for neurosis. And if a needing in sleep increasing and you are feeling not rest, and adter 10-12 hours a sleep, thus its a consequence for an especial pathologic condition, a so calling hypersomnia, as a reaction on intoxicatiion or functional changes for nerve system .Doctor will define, that you are suffering of hypersomnia or a high needing in sleep is a result for over tiredness, causing a constant destroying for life rhytm.