Workouts Help Sleep Quality

Regular exercise helps improve sleep
Diet and exercise will always be the best diagnosis a doctor can give you. Often, it’s the simple things that can help reduce your risk of sleep apnea, an increasingly common form of sleep deprivation that affects millions of Americans. Come visit the Clinic’s Sleep Center for more information regarding sleep apnea. Our world class medical staff has been helping victims of sleep apnea for decades.
Visit the Sleep Center website.

How Does Exercise Affect Sleep and Energy?

People who regularly hit the gym sleep better and feel more alert during the day than those who are not as physically active, according to a study.

The results showed that people who did 150 minutes of moderate to vigorous activity a week reported a 65-percent improvement in sleep quality.

“Physical activity may not just be good for the waistline and heart, but it also can help you sleep,” study researcher Brad Cardinal, professor of exercise science at Oregon State University, said in a statement.

Participants who worked out for at least 150 minutes also said that they felt less drowsy during the daytime, compared with those who were less physically active.

(People who got 150 minutes of exercise a week reported a 65-percent improvement in their sleep quality.)

Cardinal and his colleagues studied a nationally representative sample of more than 2,600 men and women between ages 18 and 85.The study adds to the evidence showing that “regular physical activity may serve as a non-pharmaceutical alternative to improve sleep,” Cardinal said.

The study showed that the risk of often feeling overly sleepy during the day dropped by 65 percent for the more active participants.

The study authors noted that the national guideline that recommends getting 150 minutes of moderate to vigorous activity a week was originally set to improve cardiovascular health, but their findings show that that level of exercise has other health benefits as well. Approximately 35 to 40 percent of adults in the U.S. have problems falling asleep or experience daytime sleepiness, according to the National Institutes of Health.

What If You’re Too Tired to Work Out?

The researchers also found that participants who met the physical activity guidelines were 68 percent less likely to experience leg cramps while sleeping, and 45 percent less likely to have difficulty concentrating when tired.

If you often experience daytime drowsiness, it may seem contradictory to spend even more of your lagging energy by going for a run or attending a Zumba class, but such physical exertion will actually make you feel more awake, according to the researchers.

“There are trade-offs. It may be easier when you are tired to skip the workout and go to sleep, but it may be beneficial for your long-term health to make the hard decision and get your exercise,” Cardinal said.

Pass it on: People who get at least 150 minutes of exercise a week sleep better and feel more alert during the day than those who are not as physically active.

Sleep Study Findings: Why Do We Sleep, Anyway?



Hunger and Eating/Sleepiness and Sleep: Powerful Internal Drives

A resource from the Division of Sleep Medicine at Harvard Medical School

While we might not often think about why we sleep, most of us acknowledge at some level that sleep makes us feel better. We feel more alert, more energetic, happier and better able to function following a good night of sleep. However, the fact that sleep makes us feel better and that going without sleep makes us feel worse only begins to explain why sleep might be necessary.

One way to think about the function of sleep is to compare it to another of our life-sustaining activities: eating. Hunger is a protective mechanism that has evolved to ensure that we consume the nutrients our bodies require to grow, repair tissues, and function properly. And although it is relatively easy to grasp the role that eating serves‚ÄĒ given that it involves physically consuming the substances our bodies need‚ÄĒeating and sleeping are not as different as they might seem.

Both eating and sleeping are regulated by powerful internal drives. Going without food produces the uncomfortable sensation of hunger, while going without sleep makes us feel overwhelmingly sleepy. And just as eating relieves hunger and ensures that we obtain the nutrients we need, sleeping relieves sleepiness and ensures that we obtain the sleep we need. Still, the question remains: Why do we need sleep at all? Is there a single primary function of sleep, or does sleep serve many functions?

An Unanswerable Question?

Scientists have explored the question of why we sleep from many different angles. They have examined, for example, what happens when humans or other animals are deprived of sleep. In other studies, they have looked at sleep patterns in a variety of organisms to see if similarities or differences among species might reveal something about sleep’s functions. Yet, despite decades of research and many discoveries about other aspects of sleep, the question of why we sleep has been difficult to answer.

The lack of a clear answer to this challenging question does not mean that this research has been a waste of time. In fact, we now know much more about the function of sleep, and scientists have developed several promising theories to explain why we sleep. In light of the evidence they have gathered, it seems likely that no single theory will ever be proven correct. Instead, we may find that sleep is explained by two or more of these explanations. The hope is that by better understanding why we sleep, we will learn to respect sleep’s functions more and enjoy the health benefits it affords.

This essay outlines several current theories of why we sleep. To learn more about them, be sure to check out the “Bookshelf” feature at the end of this essay. There you’ll find links to articles by researchers who are studying this fascinating question.

What are Some Theories for Why We Sleep?

Inactivity Theory

One of the earliest theories of sleep, sometimes called the adaptive or evolutionary theory, suggests that inactivity at night is an adaptation that served a survival function by keeping organisms out of harm’s way at times when they would be particularly vulnerable. The theory suggests that animals that were able to stay still and quiet during these periods of vulnerability had an advantage over other animals that remained active. These animals did not have accidents during activities in the dark, for example, and were not killed by predators. Through natural selection, this behavioral strategy presumably evolved to become what we now recognize as sleep.

A simple counter-argument to this theory is that it is always safer to remain conscious in order to be able to react to an emergency (even if lying still in the dark at night). Thus, there does not seem to be any advantage of being unconscious and asleep if safety is paramount.

Energy Conservation Theory

Although it may be less apparent to people living in societies in which food sources are plentiful, one of the strongest factors in natural selection is competition for and effective utilization of energy resources. The energy conservation theory suggests that the primary function of sleep is to reduce an individual’s energy demand and expenditure during part of the day or night, especially at times when it is least efficient to search for food.

Research has shown that energy metabolism is significantly reduced during sleep (by as much as 10 percent in humans and even more in other species). For example, both body temperature and caloric demand decrease during sleep, as compared to wakefulness. Such evidence supports the proposition that one of the primary functions of sleep is to help organisms conserve their energy resources. Many scientists consider this theory to be related to, and part of, the inactivity theory.

Restorative Theories

Another explanation for why we sleep is based on the long-held belief that sleep in some way serves to “restore” what is lost in the body while we are awake. Sleep provides an opportunity for the body to repair and rejuvenate itself. In recent years, these ideas have gained support from empirical evidence collected in human and animal studies. The most striking of these is that animals deprived entirely of sleep lose all immune function and die in just a matter of weeks. This is further supported by findings that many of the major restorative functions in the body like muscle growth, tissue repair, protein synthesis, and growth hormone release occur mostly, or in some cases only, during sleep.

Other rejuvenating aspects of sleep are specific to the brain and cognitive function. For example, while we are awake, neurons in the brain produce adenosine, a by-product of the cells’ activities. The build-up of adenosine in the brain is thought to be one factor that leads to our perception of being tired. (Incidentally, this feeling is counteracted by the use of caffeine, which blocks the actions of adenosine in the brain and keeps us alert.) Scientists think that this build-up of adenosine during wakefulness may promote the “drive to sleep.” As long as we are awake, adenosine accumulates and remains high. During sleep, the body has a chance to clear adenosine from the system, and, as a result, we feel more alert when we wake.

Brain Plasticity Theory

One of the most recent and compelling explanations for why we sleep is based on findings that sleep is correlated to changes in the structure and organization of the brain. This phenomenon, known as brain plasticity, is not entirely understood, but its connection to sleep has several critical implications. It is becoming clear, for example, that sleep plays a critical role in brain development in infants and young children. Infants spend about 13 to 14 hours per day sleeping, and about half of that time is spent in REM sleep, the stage in which most dreams occur. A link between sleep and brain plasticity is becoming clear in adults as well. This is seen in the effect that sleep and sleep deprivation have on people’s ability to learn and perform a variety of tasks.

This theory and the role of sleep in learning are covered in greater detail in Sleep, Learning, and Memory.
Although these theories remain unproven, science has made tremendous strides in discovering what happens during sleep and what mechanisms in the body control the cycles of sleep and wakefulness that help define our lives. While this research does not directly answer the question, “Why do we sleep?” it does set the stage for putting that question in a new context and generating new knowledge about this essential part of life.

For more about why we sleep, watch the video Why Sleep Matters and explore Consequences of Insufficient Sleep.

Amarillo Diagnostic Clinic is the only Sleep Center in the Panhandle area accredited by the American Academy of Sleep Medicine. Give us a call at 806-358-0200 to set up your sleep study.

Understanding Sleep Apnea: How Common Is It?


adc-understanding-sleep-apnea-infographicSleep apnea is a very common disorder in which people stop breathing during sleep. People with sleep apnea may stop breathing repeatedly during their sleep, often for a minute or longer and as many as hundreds of times during a single night.
Sleep apnea can be caused by either partial or complete obstruction of the airway (obstructive apnea) or temporary loss of the stimulation from the brain to take a breath during sleep.  As a result, the brain is forced to awaken slightly to restore normal breathing or to relieve the obstruction.  These brief awakenings lead to a substantial decrease in sleep quality.

  • Sleep apnea is very common, as common as type 2 diabetes. It affects more than 18 million Americans, according to the National Sleep Foundation.
  • Untreated, sleep apnea can cause high blood pressure and other cardiovascular disease, memory problems, weight gain, impotence, and headaches.
  • Sleep apnea is seen more frequently among men than among women, particularly African-American and Hispanic men.
  • Because of the lack of awareness by the public and health care professionals, the vast majority of sleep apnea patients remain undiagnosed and therefore untreated.

Think you might have a sleep disorder? We use the latest technology for diagnosing and treating sleep disorders in a comfortable and home-like atmosphere. Our team of sleep professionals is dedicated to providing the highest quality of sleep for our patients. Contact us if you have any questions or to schedule and appointment.

(Some information provided by the National Sleep Foundation).

Snoring: What is your body telling you?

Frustrated man and sleeping woman

Frustrated man and sleeping woman

A lack of quality sleep can manifest itself in many ways. Excessive sleepiness, for example, may be due to sleep-deprivation or may be a sign of a sleep disorder.  Sleep Apnea is often to blame. Sleep apnea is a cessation of breath during sleep, and usually occurs from a blockage in the back of the throat.

Did you know snoring may be a symptom of a serious, potentially life-threatening, condition called sleep apnea. The good news is, for most people both snoring and sleep apnea can be eliminated in one day.

The problem is much more common than many realize. In fact, approximately 40 million Americans suffer from chronic sleep disorders such as sleep apnea, narcolepsy or insomnia. An additional 20-30 million individuals experience intermittent sleep related problems.

Snoring is a common symptom that acts as an alert of sleep apnea. When snoring and sleepiness co-exist, the likelihood of sleep apnea must be considered. Snoring can be problematic, not only for the person snoring, but also for anyone nearby.

Diagnosis & Treatment

Simple, non-invasive testing can be performed to accurately diagnose many leading conditions that may cause snoring or excessive sleepiness. If treatment is necessary, it can be accomplished through a second night study. In many cases, patients will become more alert and productive the very next day, no surgery or medications required. These conditions can be very quickly corrected, resulting in an improved quality of life, as well as decreasing cardiovascular risks for heart attacks, strokes and heart irregularities.

Sleep Hygiene

The good news is that diagnosing and treating these ailments is nothing to lose sleep over. Developing healthy sleep habits will encourage a decrease or elimination in symptoms. Give these a try:

  • Avoid caffeine for six hours before bedtime
  • Avoid alcohol for two hours before bedtime
  • Avoid smoking cigarettes
  • Exercise, but not within 2 hours of bedtime
  • Maintain a regular sleep/wake cycle

Don’t stay in the dark about healthy sleep.¬†Visit the Sleep Center at ADC.¬†Other disorders can also disturb your sleep. They may include periodic movements in sleep, restless legs syndrome, nightmares, panic attacks, sleep walking, sleep talking and many others. Contact Amarillo Diagnostic Clinic to schedule an appointment..

Additional information about sleep disorders can be obtained from the American Sleep Disorders Association or by scheduling an appointment for a consultation with a sleep specialist.

ADC Sleep Disorders Center

ADC Sleep Disorders Center


Your Poor Sleep May Be Effecting Your Newborn

Sleep Apnea May Affect Birth Outcome

Diana Mahoney, Elsevier Medical News

MINNEAPOLIS – Women with sleep-disordered breathing have an increased likelihood of adverse pregnancy outcomes, but it is unclear whether the heightened risk can be attributed primarily to the breathing disorder or to obesity, reported lead investigator Dr. Francesca L. Facco.

Embed from Getty Images

Sleep disordered breathing (SBD) occurs in approximately 2% of the female population and has been linked to cardiovascular and metabolic morbidities¬†and mortality in non-pregnant¬†populations, said Dr. Facco of Northwestern University in Chicago. However, “few studies have examined the relationship between abnormal respiratory patterns or quality of ventilation during sleep in pregnancy and adverse obstetrical outcomes, which is what we sought to do in this investigation,” she said at the annual meeting of the Associated Professional Sleep Societies.

Read the full post…

Signs of Obstructive Sleep Apnea (OSA) – Infographic


Signs of Obstructive Sleep Apnea (OSA)

A Hidden Crisis: Driver Sleep Apnea

Originally Published on PPD

What is Sleep ApneaSleep apnea is very common, particularly in the commercial driver population. Studies show that up to 28% of commercial drivers may be afflicted. Primary risk factors include being male, overweight, and over the age of forty. Fortunately, sleep apnea can be diagnosed and, with treatment, quality of life and health benefits can be realized.

Also See: U.S. Department of Transportation: Sleep Apnea and Commercial Drivers

Sleep apnea is defined as the cessation of breathing during sleep. Obstructive sleep apnea (OSA) is the most common form of sleep apnea ‚Äď where the tissues in the back of the throat repetitively collapse during sleep, producing snoring and complete airway blockage. This blockage creates pauses in breathing that occur repeatedly every night. In severe cases they can occur as frequently as every 30 seconds. Alarmingly, they can last up to a full minute.

These repetitive pauses in breathing during sleep are accompanied by a reduction in blood oxygen levels and are followed by an arousal response. This response includes a release of substances into the bloodstream, which promote elevation of blood pressure, inflammation, insulin resistance, and a disruption of the brain wave sleep pattern. The consequences of untreated sleep apnea include poor quality sleep, excessive daytime fatigue and sleepiness, irritability, hard-to-control high blood pressure and diabetes, heart disease, and stroke. Interestingly, and not coincidentally, many of these same medical conditions account for the majority of health-related expenditures in the commercial driver population. Moreover, untreated sleep apnea may be responsible for job impairment and motor vehicle crashes.

U.S. Department of Transportation: Sleep Apnea and Commercial Drivers

U.S. Department of Transportation
Originally Published at U.S. Department of Transportation

Do you snore? Do you feel sleepy during the day? Are you over 40 or overweight? If you answered yes to these questions, you may be at risk for obstructive sleep apnea.

Sleep apnea is a breathing-related sleep disorder that causes brief interruptions of breathing during sleep. These pauses in breathing can last at least 10 seconds or more and can occur up to 400 times a night. Sleep apnea is a serious, potentially life-threatening condition that often goes unrecognized and undiagnosed.

Are You At Risk for Sleep Apnea?
Sleep apnea occurs in all age groups and both sexes, but there are certain factors that put you at higher risk:

  • A family history of sleep apnea
  • Being overweight
  • A large neck size (17 inches or greater for men, 16 inches or greater for women)
  • Being age 40 or older
  • Having a small upper airway
  • Having a recessed chin, small jaw or a large overbite
  • Smoking and alcohol use
  • Ethnicity

The Federal Motor Carrier Safety Administration (FMCSA) says that as many 28 percent of commercial driver’s license (CDL) holders have sleep apnea.1

Signs of sleep apnea include daytime sleepiness, falling asleep at inappropriate times, loud snoring, depression, irritability, loss of sex drive, morning headaches, frequent nighttime urination, lack of concentration, and memory impairment. For commercial drivers, these symptoms are dangerous and potentially deadly. Research indicates that untreated sleep apnea puts drivers at increased risk for motor vehicle crashes. In fact, one study found that drivers with untreated sleep apnea did worse on performance tests than healthy alert subjects whose blood alcohol concentrations was above the federal limit for driving a commercial motor vehicle (CMV).2

The good news is that sleep apnea is a highly treatable disorder. A continuous positive airway pressure machine is the most effective therapy, requiring patients to wear a nasal mask during sleep. The mask, connected to a pump, gently forces compressed air into the nasal passages at pressures high enough to open the airway from the inside. In addition, people with sleep apnea can loose weight, avoid alcohol prior to bedtime, and avoid sleeping on their backs. Other treatments include the wearing of oral devices and surgery to remove enlarged tonsils, adenoids, nasal polyps, or other growths. Deviated nasal septums or unusually formed jaws or soft palates can also be corrected surgically.

Once you have received treatment for sleep apnea and comply with your treatment plan, you can do your job as safely as someone who doesn’t have the disorder.

What should a CMV driver do after learning that they have sleep apnea?
Each state sets its own medical standards for driving a commercial motor vehicle in intrastate commerce. Many States have adopted the medical regulations found under Section 391.41(b)(5) of the FMCSRs and have determined that sleep apnea is a disqualifying condition. Each State has the jurisdictional authority to suspend a CDL if a person has sleep apnea. Medical examiners and CMV drivers should check with their Department of Motor Vehicles for more information about medical standards in their State.What level of sleep apnea (mild, moderate, severe) disqualifies a CMV driver?
The disqualifying level of sleep apnea is moderate to severe, which interferes with safe driving. The medical examiner must qualify and determine a driver’s medical fitness for duty.What are the obligations of a motor carrier concerning an employee with sleep apnea?
A motor carrier may not require or permit a driver to operate a CMV if the driver has a condition, including sleep apnea, that would affect his or her ability to safely operate the vehicle.

If you suspect that you have sleep apnea, the FMCSA and the National Sleep Foundation (NSF) urge commercial truck and motorcoach drivers to discuss the problem with their doctor.


1. Pack AI, Dinges DF, & Maislin G. (2002) A Study of Prevalence of Sleep Apnea among Commercial Truck Drivers (Report No. DOT-RT-02-030). Washington, DC: U.S. Department of Transportation, FMCSA.
2. Powell NB et al. (1999). A comparative model: reaction time performance in sleep-disordered breathing versus alcohol-impaired controls. Laryngoscope, 109(10):1648-54.


The materials contained on this page were developed under a contract with the National Sleep Foundation (NSF) and are being disseminated by the Federal Motor Carrier Safety Administration (FMCSA) in the interest of information exchange. The FMCSA assumes no liability of the contents or use thereof.

The materials contained on this page do not establish FMCSA policies or regulations, nor do they imply an endorsement or partiality by FMCSA of any product, the NSF, or the conclusions and/or recommendations contained in the materials. Trademarks or manufacturers’ names may appear herein only because they are considered essential to the object of the materials.

Sleep Apnea and the Brain

Obstructive sleep apnea, which has been linked to cognitive problems, is treatable.

Living Well, NeurologyNow, February/March 2012

Obstructive sleep apnea, which has been linked to cognitive problems, is treatable.¬†Obstructive sleep apnea (OSA) usually produces the type of loud snoring exaggerated for comic effect by cartoon characters and comedians. Homer Simpson snores operatically. So does Curly of the Three Stooges.¬†But there‚Äôs nothing funny about OSA. This common form of ‚Äúsleep-disordered breathing‚ÄĚ results when the tongue and soft palate in the back of the throat relax during sleep and block the windpipe,¬†leaving the sleeper gasping and struggling for air (for more Neurology Now coverage of OSA). Although these episodes don‚Äôt always wake up the sleeper, they often rouse a person dozens of times during the night. In either case, the person may fail to get the deep, restful sleep that restores the body and the mind. As a result of these episodes of sleep-disordered breathing, people with OSA often experience head-aches, irritability, forgetfulness, and daytime sleepiness that can be severe. People¬†with OSA are up to five times more likely¬†to be involved in a serious traffic accident. Sleep-disordered breathing, such as the kind caused by OSA, has also been associated with hypertension, heart disease, diabetes, mild cognitive impairment, and dementia.

Less Oxygen To the Brain

A recent study suggests how OSA might contribute to dementia, including Alzheimer‚Äôs disease, and to its precursor, mild cognitive impairment (MCI), defined by the U.S. National Library of Medicine as ‚Äúthe stage between normal forgetfulness due to aging and the development of dementia.‚ÄĚ People with MCI generally recognize they‚Äôre having memory problems, but the lapses do not interfere significantly with everyday activities, and not everyone with MCI develops dementia.Kristine Yaffe, M.D., member of the American Academy of Neurology (AAN) and professor of psychiatry, neurology, and epidemiology and biostatistics, and Roy and Marie Scola Endowed Chair in Psychiatry at the University of California, San Francisco, led a study that began with 298 older women who were free of cognitive problems. An overnight sleep study showed that 35 percent of them stopped breathing in their sleep 15 or more times per night. During the next five years, 44 percent of these women developed mild cognitive impairment or dementia, compared to only 31 percent of the women with normal nighttime breathing.


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Sleep Medicine with Dr. Gary Polk

Dr. Polk is a member of the Amarillo Diagnostic Clinic, P.A.

Your Sleep Study Experience

This week we have put you in the eyes of a patient taking a sleep study to show you what the experience is like.

Welcome to the ADC Sleep Center.

You have been scheduled for a sleep study. You will be scheduled to begin between 8-9:30PM.

Feel free to bring your normal toiletries and sleep wear. You may also bring your own pillow. Your sleep experience will start with paperwork which allows you to tell us how you’ve spent your day.

To determine if a sleep disorder exists, your physician will need to know what body function changes occur during your night of sleep. They do this by attaching several monitoring sensors to your body.This process takes approx. 30 minutes and allows you time to ask any questions that you may have.

  • Our first goal will be to determine when you go to sleep and what stages of sleep you reach.¬†We do this by recording your brainwave patterns as well as your eye movements.
  • We monitor your heart rate to see if you have any irregular heart beats during your sleep.
  • A sensor on your finger will monitor if your body is receiving the amount of oxygen it needs.
  • One of the most common reasons a sleep study happens is because of snoring. To measure, we will apply a small microphone to your neck.
  • Often people will have leg movements at night, which can disrupt your sleep. We will put sensors on your shins to measure this.
  • We‚Äôll monitor your air flow to see if you stop breathing during the night.¬†If the technician notices abnormal breathing patterns, they may awaken you early in the study to apply a breathing mask for the night which will ensure normal breathing patterns.

An intercom in the room will allow for communication in case you have any questions or need to go to the bathroom during the night. Technicians will be available throughout your study but will not disturb you unless absolutely necessary.

Your study will conclude at around 6am the next morning. Congratulations, you have completed your sleep study, and we will schedule a meeting to review your results.

What next?

Check out the video below to see what you will learn from your sleep study.

Call us at 806.356.5522 or check out or website to learn more about our Sleep Center.