Myths and Misconceptions about Sleep
Historically, our Naval fleet culture has not fully appreciated the value of crew rest. Many of us have heard claims about sleep requirements that have long been discredited by scientific research. Some common myths regarding our sleep needs and performance include these facts from the National Sleep Foundation:
1. Snoring is a common problem, especially among men, but it isn’t harmful.
Although snoring may be harmless for most people, it can be a symptom of a life-threatening sleep disorder called "sleep apnea", especially if it is accompanied by severe daytime sleepiness. Sleep apnea is characterized by pauses in breathing that prevent air from flowing into or out of a sleeping person’s airways. People with sleep apnea awaken frequently during the night gasping for breath. The problem results in reduced blood oxygen levels, can strain the heart and cardiovascular system, and increase the risk of cardiovascular disease. Snoring on a frequent or regular basis has been directly associated with hypertension. Obesity and a large neck can contribute to sleep apnea. Sleep apnea can be treated; men and women who snore loudly, especially if pauses in the snoring are noted, should consult a physician.
2. You can "cheat" on the amount of sleep you get.
Sleep experts say most adults need between seven to nine hours of sleep each night for optimum performance, health and safety. When we don't get adequate sleep, we accumulate a sleep debt that can be difficult to "pay back" if it becomes too big. The resulting sleep deprivation has been linked to health problems such as obesity and high blood pressure, negative mood and behavior, decreased productivity, and safety issues in the home, on the job, and on the road.
3. Turning up the radio, opening the window, or turning on the air conditioner are effective ways to stay awake when driving.
These "aids" are ineffective and can be dangerous to the person who is driving while feeling drowsy or sleepy. If you're feeling tired while driving, the best thing to do is to pull off the road in a safe rest area and take a nap for 15-45 minutes. Caffeinated beverages can help overcome drowsiness for a short period of time. However, it takes about 30 minutes before the effects are felt. The best prevention for drowsy driving is a good night’s sleep the night before your trip.
4. Teens (in the US Navy, these are young enlisted and young JOs) who fall asleep in class (on watch) have bad habits and/or are lazy.
According to sleep experts, teens (ages 14 to early 20s) need at least 8 to 10 hours of sleep each night, compared to an average of seven to nine hours each night for most adults. Their internal biological clocks also keep them awake later in the evening and keep them sleeping later in the morning. However, many schools begin classes early in the morning, when a teenager's body wants to be asleep. As a result, many teens come to school too sleepy to learn, through no fault of their own. This same problem exists for young servicemembers who are getting much less sleep than itheir bodies require. Their sleep debt is even greater than their adult counterparts who needabout an hour less sleep each night.
5. Insomnia is characterized by difficulty falling asleep.
Difficulty falling asleep is but one of four symptoms generally associated with insomnia. The others include waking up too early and not being able to fall back asleep, frequent awakenings, and waking up feeling unrefreshed. Insomnia can be a symptom of a sleep disorder or other medical or psychological/psychiatric problem, and can often be treated. According to the National Sleep Foundation's 2002 Sleep in America poll, 58 percent of adults in this country reported at least one symptom of insomnia in the past year. When insomnia symptoms occur more than a few times a week and impact a person’s daytime functions, the symptoms should be discussed with a doctor or other health care provider.
6. Daytime sleepiness always means a person isn't getting enough sleep.
Excessive daytime sleepiness is a condition in which an individual feels very drowsy during the day and has an urge to fall asleep when he/she should be fully alert and awake. The condition, which can occur even after getting enough nighttime sleep, can be a sign of an underlying medical condition or sleep disorder such as narcolepsy or sleep apnea. These problems can often be treated, and symptoms should be discussed with a physician. Daytime sleepiness can be dangerous and puts a person at risk for drowsy driving, injury, and illness and can impair mental abilities, emotions, and performance.
7. Health problems such as obesity, diabetes, hypertension, and depression are unrelated to the amount and quality of a person's sleep.
Studies have found a relationship between the quantity and quality of one's sleep and many health problems. For example, insufficient sleep affects growth hormone secretion that is linked to obesity; as the amount of hormone secretion decreases, the chance for weight gain increases. Blood pressure usually falls during the sleep cycle, however, interrupted sleep can adversely affect this normal decline, leading to hypertension and cardiovascular problems. Research has also shown that insufficient sleep impairs the body's ability to use insulin, which can lead to the onset of diabetes. More and more scientific studies are showing correlations between poor and insufficient sleep and disease.
8. The older you get, the fewer hours of sleep you need.
Sleep experts recommend a range of seven to nine hours of sleep for the average adult. While sleep patterns change as we age, the amount of sleep we need generally does not. Older people may wake more frequently through the night and may actually get less nighttime sleep, but their sleep need is no less than younger adults. Because they may sleep less during the night, older people tend to sleep more during the day. Naps planned as part of a regular daily routine can be useful in promoting wakefulness after the person awakens.
9. During sleep, your brain rests.
The body rests during sleep, however, the brain remains active, gets "recharged," and still controls many body functions including breathing. When we sleep, we typically drift between two sleep states, REM (rapid eye movement) and non-REM, in 90-minute cycles. Non-REM sleep has four stages with distinct features, ranging from stage one drowsiness, when one can be easily awakened, to "deep sleep" stages three and four, when awakenings are more difficult and where the most positive and restorative effects of sleep occur. However, even in the deepest non-REM sleep, our minds can still process information. REM sleep is an active sleep where dreams occur, breathing and heart rate increase and become irregular, muscles relax and eyes move back and forth under the eyelids.
10. If you wake up in the middle of the night, it is best to lie in bed, count sheep, or toss and turn until you eventually fall back asleep.
Waking up in the middle of the night and not being able to go back to sleep is a symptom of insomnia. Relaxing imagery or thoughts may help to induce sleep more than counting sheep, which some research suggests may be more distracting than relaxing. Whichever technique is used, most experts agree that if you do not fall back asleep within 15-20 minutes, you should get out of bed, go to another room and engage in a relaxing activity such as listening to music or reading. Return to bed when you feel sleepy. Avoid watching the clock.
Recognizing your own circadian rhythms and understanding the relationship between sleep and performance is the first step in implementing a sound Crew Endurance policy.