Sleep is a state of partial or full unconsciousness, and must be achieved for the body and mind to rest and be restored. In general, we need seven to nine hours sleep every 24 hours. Any less can cause the onset of fatigue.
When you do not get enough sleep – sleep deprivation – your mental and physical performance is reduced. Sleep loss can be cumulative and over time a sleep debt builds. For example, if you need eight hours sleep per day and only manage six hours over four days, then you have accumulated an eight hour sleep debt.
What effect does this have? Recent research indicates the effect of 17 to 24 hours of wakefulness is the equivalent of a blood alcohol concentration of 0.05% – 0.10%. The current NZ legal limit for driving is 0.08% – 80 mcg of alcohol to 100 ml of blood. This limit will reduce in December 2014 to 0.05%, which is 50 mcg of alcohol per 100 ml of blood.
Quality and quantity of sleep is important. They are determined by your activities and timing during the 24-hour cycle. Humans are programmed to be active during the day and sleep at night. Shift work or night rosters disturb your body clock.
Sleep inertia is a feeling of disorientation and reduced alertness when you first wake up. This can impact your performance and has been identified as a factor in several accidents and incidents.
There is a very popular smartphone app that claims to be able to monitor your sleep patterns and then wake you when in your lightest phase of sleep. Thereby eliminating sleep inertia. You can find this here http://www.sleepcycle.com/
Micro sleeps are very short periods of sleep, typically less than 3 seconds, that happen when you are fatigued and try to stay awake to perform a monotonous task. You will not know that you have been asleep, but your blank stare and head snapping will alert others.
Other disruptions to sleep, such as sleep apnoea and insomnia are treatable. Talk to your doctor for advice on this.
How can you get the sleep you need? There are a number of things you can do. A bed is a good start. Make sure that the bedroom is just that, designed for sleeping. Keep it this way by taking out all the non-essential sleep items such as computers and workout equipment. You need a quiet, dark area, especially if you are away from home.