The hustle and bustle of modern living can take its toll on how we feel and perform during our awake time, but our “down” time is just as active and important. Sleep, considered by most to be that respite from our daily routine, is actually a very active, very busy time for our nervous system. The hustle and bustle of modern living can take its toll on how we feel and how we perform during our awake time. During our waking hours, as our nervous systems are focused on dealing with the day-to-day goings-on in our environment, our internal computers are busy taking in, interpreting and reacting to data coming in from external stimuli. In contrast, during our downtime, the biochemical activity of our internal computer takes on a different, but no less dynamic, course of action.
If you’ve ever caught yourself drifting off during a meeting, “zoning out” at a stoplight, or feeling drowsy during the day, it’s likely that you are not getting enough sleep. Sleep truly is as essential for our well-being as food or water. Research has shown that without proper amounts of sleep, normal waking functions can be slowed or compromised. Performance variables such as reaction-time, emotional response to environmental stressors, sense of well-being or ability to think, processing data and making accurate, appropriate decisions, can be impacted. How well we cope and handle the normal challenges of day-to-day life are impacted by both the quality and quantity of our regular sleep pattens. It is essential for the normal, healthy performance of activities of daily life that we get sufficient sleep.
Sleep is a bodily state of partial or full unconsciousness, during which voluntary functions, physical and mental, are suspended, and the body rests. Sleep is not an inactive state for the body, however. It is during time that the body is busy rebuilding and replenishing its supply of critical chemical messengers, called neurotransmitters, in the brain and the nervous system.
These neurotransmitters are the chemical communicators of the body. It is through the neurotransmitters that the brain and central nervous system control and regulate all body functions. It is clear, then, that sleep and the replenishment of these neurotransmitters is essential for proper body functioning.
In humans, sleep can be divided into two general stages, the REM (rapid eye movement) stage and the NREM (non-rapid eye movement) stage. NREM sleep can be broken down further into stages. As we enter into the sleep state we progress through 3 stages ending up in what’s called “slow wave”, or deep sleep. It’s here that the greatest degree of brain and body healing takes place including the release of deep seated “neural stress”, and then the important recharging of tired brain cells.
Unfortunately, as we age the brain gets less deep sleep leading to more stress and anxiety during the day. After deep sleep the brain cycles back into REM, or rapid eye movement. It is during REM sleep that the body enters a deep dream-state, during which time the muscles of the body also experience a temporary natural paralysis, called atonia. REM sleep typically makes up about 25% of the total sleep time for most people.
The amount of sleep needed for optimal health and functioning varies from individual to individual. However, it is estimated that the majority of Americans today, given our constant “go-go-go” lifestyles, are sleep-deprived to some extent. It has been shown that the people who get between 6-7 hours of sleep per day were associated with lower mortality. Lack of sleep has been shown to increase risk of cardiovascular disease, hypertension, diabetes, mood disorders such as depression, and has even been correlated with cancer. On the other hand, too much sleep has also been associated with various indicators of poor health. Most experts seem to agree that somewhere around seven hours of sleep is sufficient for optimal health for most people. While we sleep, the body is busy repairing, rebuilding, and replenishing the internal biochemical environment. A myriad of activity occurs during the sleep state, involving all systems of the body. The body’s major restorative functions such as muscle growth and tissue repair, protein synthesis, and growth hormone release occur mostly during sleep time.
The immune system and immune function are bolstered while we sleep. It has been shown that people who get less sleep tend to be more susceptible to infection. Individuals who get sufficient sleep suffer less from the negative impact of stress, resulting in less heart disease and stroke. Memory and brain function chemicals (called neurotransmitters) are replenished during sleep. These neurotransmitters include dopamine, adrenalin, noradrenalin, acetylcholine and serotonin. Because these chemicals are responsible for the transmission and modulation of signals between neurons and other body cells, they are critical for healthy, optimal body functioning. These chemicals govern functions such as focus, memory, alertness and responsiveness, emotional response and overall energy as well as physical function on all levels.
During normal daily functions and activity, neurotransmitters are used to transmit nerve impulses along the entire nervous system. As normal daily life wears on, and especially during stressful periods, these brain chemicals can be depleted. It is during sleep time that levels of these chemicals are replenished. Without sufficient sleep, our neurotransmitter “pools” become chronically depleted, resulting in the compromise of many important brain and body functions. Only sleeping allows your body to replenish healthy levels of these neurotransmitters, in order for the body to function properly.
Sleep is vital for optimal health and well- being. The sleep period is the time when the body re-fortifies itself, repairs and replenishes its entire system. Without sufficient sleep, the body becomes increasingly susceptible to illness and infection, compromised physical and mental function, and even mood and emotional disturbances. Focus on the quality of your sleep time as much as you focus on your waking life, and you’ll see an increased quality of living and performance!
See other articles, Healthy Tips on Getting Good Sleep and Preventing Iron Deficiency
Marshall et al., 2006, as cited in Walker, M.P. (2009). “The Role of Sleep in Cognition and Emotion”. Annals of the New York Academy of Sciences 1156: 174.
Patel, SR; Ayas, NT; Malhotra, MR; White, DP; Schernhammer, ES; Speizer, FE; Stampfer, MJ; Hu, FB (May 2004). “A prospective study of sleep duration and mortality risk in women”. Sleep 27 (3): 440–4.
Patel SR, Malhotra A, Gottlieb DJ, White DP, Hu FB (July 2006). “Correlates of long sleep duration”. Sleep 29 (7): 881–9.
Irwin MR, Ziegler M (February 2005). “Sleep deprivation potentiates activation of cardiovascular and catecholamine responses in abstinent alcoholics”. Hypertension 45 (2): 252–7.
Charles Weller
Author