We need sleep to stay healthy, and to be alert and functioning during the day.
Scientists used to believe that the brain was inactive during sleep – that as sensory input slowed or stopped, so did brain activity. We now know that a lot goes on when we’re sleeping.
A typical good night’s sleep requires going through a series of sleep cycles every night.
A cycle begins the moment you close your eyes. Your brain almost immediately begins to increase its production of Alpha waves. As you relax and become drowsy, your Alpha waves increase and deepen, releasing calming neuro chemicals as you gradually enter into Theta waves.
It’s at this crossover point into Theta that you actually drift off to sleep and release consciousness of the outside world. As with Alpha waves, the Theta waves deepen and increase.
At the slower Alpha and Theta brainwave patterns, production of DHEA and other healing hormones increase significantly, enabling the body to be vibrant, healthy, and able to combat disease effectively.
DHEA, is produced by your adrenal glands and is a source ingredient to virtually every hormone your body needs.
Gradually you drop down through Theta and enter Delta. The deeper Theta levels and Delta are where your body starts to release greater amounts of Human Growth Hormone (HGH) and Melatonin.
HGH is nature’s way of keeping you young and healthy by repairing tissues and organs, such as stimulating the liver to purge itself of accumulated toxins.
Melatonin is a ubiquitous neurohormone whose production is low during the day and high at night. It passes through cell membranes and acts as a highly potent antioxidant to scavenge free radicals that cause damage to DNA, Reiter (1995).
Hence melatonin reduction is involved with diseases produced by free radicals, including cancer, aging, neurological diseases, acute heart disease and heart attack, Reiter and Robinson (1995).
Delta sleep is where you get your deepest, most recuperative rest and it is critical to rejuvenation of both mind and body. This may sound technical, but stay with me because it is vital that you understand the importance of a healthy sleep cycle.
You remain in Delta for a time and then begin the climb back up through the various brainwave levels in reverse order. When you get back up to the Alpha level again this completes one sleep cycle.
It varies from individual to individual but a normal sleep cycle usually takes around 95 minutes to complete before it begins all over again. But each sleep cycle is different in one very critical way.
The time you spend in the Delta wave level decreases with each successive cycle.
Perhaps in your first cycle you spend 30 or 40 minutes in Delta out of a 90 minute cycle. On the next cycle you may only spend 20 to 25 minutes in Delta. And on the next cycle perhaps you spend only 15 minutes there. Each cycle remains the same length overall but your Delta time decreases.
That means your first two or three sleep cycles each night are probably the most critical.
If, for example, you regularly go to bed about 10pm, then your body gets in its first 3 sleep cycles between the hours of 10pm and about 2am.
Most of your body’s healing and rejuvenation take place during this period.
If you take one night and stay up until 1am before going to sleep your body doesn’t simply rotate its internal clock forward 3 hours and begin your first sleep cycle at 1am.
It skips the cycles it would have had during those first 3 hours and picks up with the shorter Delta cycles just as if you had been asleep during the first 3 hours.
So in a nutshell, you simply miss those earlier cycles and the restorative sleep they bring. You can get away with this for a couple of days but try it for much longer than that you begin to function less and less well during the day. You also dramatically decrease the production of the above vital hormones.
You probably now know 99% more than most people about the sleep cycle… however, next Wednesday discover how alcohol consumption can prevent the brain from moving into certain levels of brainwaves.