what is sleep? why do we sleep? these are the rare questions one will ask, as no one has much time to think about it. Get ready to explore the secrets of sleep.
Sleep is the condition of body and mind, which will be off for several hours, where the nervous system will be shut down, eyes will be closed, muscles will be relaxed and consciousness is suspended.
It’s all done and controlled by one hormone which is called Melatonin (this hormone is behind the Secrets of sleep). This hormone is made by the pineal gland which is a small gland in the brain. Just like the sun rises in the morning and sets at night, the pineal is inactive in morning and active at nights. When the sun goes down and darkness occurs the pineal gland gets activated and start actively producing melatonin, which is released into the blood.
How many of you know that your body has its own internal clock to control the cycle of sleeping and waking? Your body clock controls how much melatonin your body makes, normally it begin to rise in the mid to late evening and remain high for most of the night, and drops in the early morning.
Normally a teen needs at least 8 hours of sleep and on average 9 hours. If sleep is cut short the body doesn’t have time to complete all of the phases needed for muscle repair, memory consolidation and release of hormones regulating growth and appetite. Then we wake up less prepared to concentrate, make decisions, or engage fully in activities.
There are 2 types of sleep namely NREM and REM, and NREM has 4 stages in it and it will be 75% of the type we experience every day and REM is only 25%. As we begin to fall asleep, we enter NREM sleep,
- Between being awake and falling asleep
- Light sleep
- Onset of sleep
- Becoming disengaged from surroundings
- Breathing and heart rate are regular
- Body temperature drops (so sleeping in a cool room is helpful)
Stages 3 and 4
- Deepest and most restorative sleep
- Blood pressure drops
- Breathing becomes slower
- Muscles are relaxed
- Blood supply to muscles increases
- Tissue growth and repair occurs
- Energy is restored
- Hormones are released, such as Growth hormone, essential for growth and development, including muscle development.
First occurs about 90 minutes after falling asleep and recurs about every 90 minutes, getting longer later in the night
- Provides energy to brain and body
- Supports daytime performance
- Brain is active and dreams occur
- Eyes dart back
Effects of sleeplessness –
- affect your memory
- affect your learning
- affect your thinking abilities
- Lack of concentration and focus
- Inability to handle stress
- heart attack & stroke
Advantages of proper sleep – Secrets of sleep
- keeps your heart healthy
- Sleep may prevent cancer
- makes you more alert
- may help you lose weight
- improves your memory
- may reduce your risk for depression
- helps the body repair itself
- reduces stress
As medically, a human can survive 11 days maximum without sleep.