When I was a young and inexperienced personal trainer, I used to think diet, supplementation, and a solid exercise program were all you needed to get and stay in shape. I overlooked the importance of sleep.

With experience, I’ve come to realize that sleep is often the deciding factor in whether or not someone succeeds.

You’ll spend more of your life sleeping than doing any other activity, so you have to get it right if you want to maintain your health.

Here’s everything you need to know to master the art of sleep.

How Sleep Works

You aren’t conscious of it, but your body is hard at work while you sleep, physically and mentally rebuilding and repairing itself.

Like the foreman on a job site, who directs and organizes electricians, carpenters, and plumbers in a methodical process, so they don’t interferes with one another’s work, your body divides sleep into different segments, so it can effectively address one part of the body, and then move onto another.

Throughout the night, your brain cycles through three stages of sleep: light, deep, and rapid eye movement (REM) sleep.

Each cycle lasts about 90 minutes, so with normal sleep, you go through four to six cycles per night. Your sleep quality is determined by the amount of time you’re in deep and REM sleep, not just by the time you spend with your eyes shut.

Most adults sleep in one, large block of time, which is also called a “monophasic” sleep pattern.

Children and the elderly do best with a “biphasic” sleep pattern, meaning they need a nap in the middle of the day to complement their nighttime slumber.

How Much Sleep Do You Need?

GroupAgesIdeal Sleep
Older Adult65+7-8
Adult18-647-9
Teenager14-178-10
School Age6-139-11
Preschool3-510-13
Toddler1-211-14
Infant4-11 months12-15
Newborn0-3 months14-17

Light Sleep

During light sleep, you’re semi-conscious. You’re aware of your environment, but only respond to something unexpected, such as the creaking of a door or your spouse whispering seductively in your ear.

You have enough awareness to make sense of what’s happening, but are asleep enough that you’re often unmotivated to move unless you sense a threat, or you’re a newlywed.

When you’re under a heavy amount of stress, you can spend most of your night in this phase, and miss out on the benefits of the next two phases.

Deep Sleep

Deep sleep supports growth and repair of your body.

Provided you remain in light sleep without interruption, 10-30 minutes later, you enter deep sleep.

Deep sleep supports your body’s physical recovery, whereas REM sleep supports your brain and mind.

A burglar would have the best chance of stealing something in this stage because you don’t hear anything, and your muscles are temporarily paralyzed.

You even lose your ability to regulate your body temperature, which is why it’s so important to sleep in a cool bedroom whenever possible.

During deep sleep, growth hormone rises, supporting tissue repair, fat metabolism, and a number of other positive health effects.

Though dreams sometimes occur during deep sleep, it is rare.

In a typical night, you enter deep sleep three to five times.

Rapid-Eye Movement (REM) Sleep

REM sleep supports growth and repair of your brain.

The last third of the night, assuming you get a full night’s sleep, is dominated by REM sleep. In total, it makes up 20-25% of your sleep time.

REM, which follows deep sleep, is your dream state (it was also a great band in the 80’s and 90’s).

Your vibrant, funny, terrifying, exciting, and disturbing dreams occur during REM sleep.

It’s in REM that your brain tries to make sense of the information from the previous day, and deal with anything that’s been on your mind. Your memories are consolidated, and your brain is actually “washed” in cerebral fluid to help remove toxins.

REM sleep time varies throughout the seasons. The average person gets about 16% more REM sleep in the winter than in the middle of the summer.

Neurogenesis, the growth of new brain cells, takes place during REM. Throughout life, we lose and rebuild brain cells, but chronic sleep deprivation limits the brain’s ability to generate new brain cells.

Interestingly, penile erection and clitoral swelling occur during REM sleep as well. For guys, lack of a morning erection is a sign of either low testosterone, or insufficient REM sleep.

Feel free to share that bit of trivia the next time you’re out with friends.

What Happens During Sleep?

The following table outlines what happens with your hormones and neurotransmitters at night.

Growth HormoneHighest secretion of 24-hour cycle occurs during deep sleep, and is secreted in pulses with each cycle back into deep sleep.
ProlactinRises 30-90 minutes after onset of sleep.
Thyroid Stimulating Hormone (TSH)Peaks in evening before sleep, and decreases throughout the night, suggesting that thyroid hormones (T3 & T4) rise as night progresses.
TestosteroneIn men, secretion is lowest at ~8 pm, and peaks about 8 am (which is why it’s best to get blood testing done first thing in the morning).
MelatoninRise begins at bedtime and peaks between 3 am-5 am.
LeptinIncreases to curb appetite.
Cortisol, Epinephrine, NorepinephrineStress hormone and neurotransmitters decrease during sleep, and rise leading into the morning wakeup time.

Melatonin

You can’t have a conversation about sleep without bringing up melatonin. Melatonin is the hormone of darkness. It’s created from the amino acid l-tryptophan.

The pineal gland secretes melatonin at dusk, and levels continue to rise until mid-morning. Moderate levels of stress or exercise enhance your ability to secrete melatonin, but it’s cyclical ebb and flow is often disrupted in people with poor or inconsistent sleep patterns.

Melatonin secretion decreases with age, which could be part of the reason older adults sleep less.

Melatonin supplementation can be beneficial when traveling across time zones, adjusting to a new sleep schedule, or for older adults.

In addition to supporting sleep, melatonin has been shown to support healthy cholesterol levels, normal inflammatory levels, and can support restful sleep, especially in those with neurodegenerative diseases, depression, chronic fatigue, fibromyalgia, headaches, and insomnia.*

I use and recommend either Sleep Essence from Young Living, or Thorne Melatonin.

Consequences of Sleep Debt

“You don’t need so much sleep. Sleep when you’re dead.”

The first time I heard that ridiculous piece of advice, I was in the locker room at the Olympic Training Center in Lake Placid. I’d asked one of the ski jumpers on the U.S. Olympic team how he fit in all his training while going to school and still having plenty of time for fun.

Unfortunately, I’ve heard people say the same thing too often to count over the years.

In some messed up way, we often thing that we can outsmart our own physiology. That the health risks of insufficient sleep don’t apply to us. If that’s what you believe, it’s time to stop deceiving yourself.

The term “sleep debt” paints an accurate picture of what you do to your body when you either sleep too few hours each night, or when you get enough hours, but you don’t achieve deep, restorative sleep.

Effects Of Sleep Debt
Elevated CholesterolReduced Testosterone
Insulin ResistanceObesity
Metabolic SyndromeType II Diabetes
Elevated CortisolMuscle Loss
Increased Appetite From Leptin & Ghrelin DysfunctionDisrupted Gut Bacteria
DepressionIncreased Inflammation
Reduced Immune FunctionIncreased Pain Sensitivity
Decreased Libido

In the past, it was thought that people who got insufficient sleep ate more and moved less, and that caused weight gain.

It turns out, weight gain isn’t necessarily a result of excess calorie intake and too little movement.

In fact, insomnia actually increases metabolic rate. One study showed a year of insomnia increased resting metabolic rate by a whopping 11%!

Yet, even though insomnia raises metabolic rate, those with insomnia still tend to get fat, even when they eat well and exercise appropriately. That sure shoots another hole in the “calories in, calories out” hypothesis.

Weight gain from sleep debt isn’t a calorie balance problem. It is a hormonal balance problem.

One night of disrupted sleep causes insulin resistance the next day.

Two nights of insufficient sleep causes mood deterioration, which is caused by dysfunction in the medial prefrontal cortex (MPFC).

A week of getting only five hours of sleep decreased testosterone by 10-15% in men.

In women with sleep debt, for each additional hour of sleep they got, their likelihood of having sex the next day increased by 14%, suggesting sleep debt robs you of your libido.

Animal research shows sleep debt increases sensitivity to pain, meaning as you lose sleep, aches, pains, and conditions like fibromyalgia can get worse.

The liver produces more than 600 metabolites. About 60% of them depend on a normal circadian rhythm.

Long-term sleep debt causes cognitive decline. Also, many neurodegenerative diseases like Alzheimer’s or Lewy Body dementia cause reductions in deep and REM sleep. The loss of REM sleep further contributes to cognitive decline.

SHIFT WORK

Cortisol is at the crux of the shift work problem. Your cortisol should reach its peak once per day, just as you wake up. However, if you wake up at one time for a job during the work week, and a totally different time on the weekends, you disrupt the normal cortisol rhythm and cause chronically elevated levels.

Constantly elevated cortisol levels cause weight gain, especially in the belly, along with muscle loss, increased heart disease risk, inflammation, immune system suppression, cognitive dysfunction, and mood changes.

If you are a shift-worker and want to maintain your health and avoid obesity, you must stick to a consistent, seven hour (or more) sleep schedule with a consistent bedtime every day, and avoid the temptation to snack on convenience foods and energy drinks.

While you can use supplements and nutrition to minimize the negative impact of shift work, sticking to a consistent schedule is the most important.

Causes of Sleep Debt, and What You Can Do About It

Your body has an internal clock which, when it’s working well, determines the ebbs and flows of hormones and neurotransmitters, manages many of your body’s systems, and guides you to sleep, wake up, nap, and move. Your internal clock is found in the suprachiasmatic nucleus (SCN).

Your environment also affects your circadian rhythm. The external influences on your circadian rhythm are called Zeitbergers. Light is the most powerful zeitberger, but diet, exercise, and supplementation also influence the SCN.

You don’t want to mess with your circadian rhythm. To give you an idea of what one lost night of sleep can do, look at the effects of shifting the clocks forward one hour for Daylight Savings Time:

Heart attack rates jump 25% the Monday after the clocks change to Daylight Savings Time.

Most of the causes of sleep debt below directly, or indirectly affect the SCN. I’ve listed the causes of sleep debt, starting with the most obvious, and ending with causes you might not think of. Often, it’s the obvious causes people overlook.

Your Bedtime Is Inconsistent

For your circadian rhythm to have a rhythm, you have to be consistent about when you go to sleep.

Melatonin secretion initiates the process of putting you to sleep. But if you keep yourself up with artificial lights, digital screens, and stimulants, eventually your body stops producing melatonin like it’s supposed to. Then, when you want to go to sleep on schedule, you won’t be able to.

When improving sleep, the most important thing you can do is to go to bed at a consistent time every night.

If you have a hard time falling asleep, read a book. Your brain waves while reading are similar to sleeping, which is probably why so many people find it easy to fall asleep after a few pages of reading, but can stay awake for hours while watching a movie in bed.

Your Bedroom Is Too Hot

By “too hot,” I’m not referring to what happens before you go to sleep in your bedroom. That activity can actually help you sleep (more on this in a future article). I’m referring to your bedroom temperature.

The ideal temperature for sleep is 67-69 degrees Fahrenheit. If you want to take things to a whole other level, I’ve heard nothing but great things about the ChiliPad, although Vanessa and I have not yet gotten one. It helps cool you from underneath, rather than just sleeping with a cooler air temperature.

Our sleep is typically great as long as we remember to turn down the thermostat, take our supplements, and eat early enough.

It is possible to go too low with the temperature, though. Doing so reduces REM sleep. This is a survival mechanism common among mammals. You wouldn’t want to be dead to the world because you’re in a dream while your body is literally freezing to death.

You Drink Too Much

If you imbibe to settle your nerves and calm your mind, it might help you fall asleep, but it can negatively affect the benefits of sleep.

Drinking “every once in a while,” compromises your REM sleep the night you drink. Interestingly, those who drink every night seem to regain their REM sleep as they develop a tolerance to alcohol. So, periodic alcohol consumption compromises REM sleep, but regular drinking does not.

However, before you justify getting jingled each night, know this: Regular drinking suppresses growth hormone. Low growth hormone leads to muscle loss and fat gain, which explains why regular drinkers often end up with big (a.k.a. “beer”) bellies and scrawny arms and legs.

You Sleep With A Disruptive Bed Partner

Whenever I get a cold, I sleep on the couch. Whenever Vanessa gets a cold…I sleep on the couch (We do have an extra bedroom, but I never sleep in there because I don’t want to make the bed in the morning).

If you sleep with someone who snores, coughs, tosses and turns, or has restless leg syndrome, you’re going to pay for it with interrupted sleep.

While I’m not a fan of having separate bedrooms, if your significant other wakes you up throughout the night, your ability to spoon him or her won’t be worth the sacrificed sleep.

Try ear plugs to drown out the noise. Have them take magnesium to reduce the restless legs. Do whatever you can, and whatever they’re willing to do to be a better bed partner. But don’t sacrifice sleep night after night if they can’t stay still and silent.

Sleep Apnea

It’s estimated that half of adult women, and a significant percentage of men today suffer from sleep apnea.

Excessive body fat is the most common cause of sleep apnea. As people gain excessive body fat, their necks and throats gain fat too.

The extra fat presses down on the soft tissue in their mouth and throat as they sleep, blocking air flow. Most of the time, the lack of oxygen wakes them up. This happens multiple times each night, causing interrupted sleep, which contributes even more to their weight gain.

While a CPAP is helpful, it is not the long-term solution. If you’re overweight and have sleep apnea, using a CPAP is like someone with type II diabetes using insulin. It deals with the symptom, but does nothing to fix the cause.

Lose the weight so you can breathe when you sleep.

Stress

In many ways, the word stress has become as bastardized as the word struggle. Perhaps it’s because most of us have never faced major stressors. Or, it could be that we have so many minor inconveniences we fret about, that our minds feel overwhelmed with irritation. Then again, it could also be the fact that so many people describe their lives as stressful, that we feel we have to exaggerate our own issues just to fit in, or one-up someone else on social media.

I digress…my point is that when it comes to stress, it isn’t really the events or circumstances themselves that cause stress. It is our interpretation and perspective of those situations.

If you want to improve your sleep quality, the solution is not to eliminate stress. It is to become better at dealing with it.

You can meditate, pray, or take a long walk as a mental break from your stress. But, if there’s something you can do about it, you need to do it. If there isn’t, then you have to let it go. Read also: 5 Ways Your Feelings Fail You (And Keep You From Living Up To Your Potential).

Holding onto stress, and the emotions that accompany it, causes a cascade of hormones and neurotransmitters that keep you from sleeping well, and further disrupt your metabolism.

While you work out the details on how you’ll handle the stress, the following supplements have been shown to help reduce feelings of stress, calm your mind, and/or support more restful sleep. The more quality sleep you get, the more resilient you become to the stressors you face.

Relora: Relora® is a combination of Magnolia and Phellodendron extracts. I was first introduced to Relora by Dr. Jim LaValle, author of Cracking the Metabolic Code. Relora has been shown to support normal stress hormone levels, relieve feelings of tension, anger and fatigue, and supports feelings of vigor and good mood.* I use and recommend Relora Plus from Thorne.

Essential Oils: A number of essential oils have shown promise in supporting a normal stress response, calming the mind, and supporting sleep, including bergamot, orange, lavender, lemon, rose, cedar, Roman chamomile, angelica, and ravensara.

Magnesium: Magnesium has numerous effects on the body and brain, one of which is to help calm the mind.

Low magnesium levels dampen serotonin production, so if your magnesium is low, supplementing with magnesium glycinate may help you calm your mind and get to sleep.*

Hemp Oil: Smoking dope could help you sleep, but the recreational use of marijuana doesn’t really fit with the Tenacious Pursuit of Optimal Health I’m going for on this site. However, you can get most of the benefits of Mary Jane, including the support of sleep, without needing to spark a bowl. Use Hemp Oil.

Hemp oil, and other phytocannabinoids have been shown to reduce feelings of stress and support better sleep. I recommend Thorne’s Hemp Oil+ as Thorne has an impeccable record for delivering pure, efficacious products, and setting the standard for product quality in the supplement industry.

Melatonin stimulates brown adipose tissue while inhibiting insulin production from the beta-cell (insulin-secreting cells of the pancreas): by doing so, melatonin may control body weight via changes in body temperature and energy expenditure whereas, by inhibiting insulin production at night, may favor beta-cell rest. We suggest that prolonging our days with artificial light may favor obesity by inhibiting melatonin production, thus silencing the brown adipose tissue, and may also impair insulin production in the long-term by prematurely exhausting the beta-cell.”

– Cizza, et al.

Stimulants

Coffee is good for you, but not when you drink it too late in the day. At least, it’s not a good idea to drink caffeinated coffee too late in the day. More often, the issue isn’t coffee, though. It’s other stimulants like energy drinks and and pre-workout supplements.

The top consumers of energy drinks are adolescents, but many adults rely on energy drinks as well. Often, the energy drinks create a faster and greater mental stimulation, and a faster and greater crash, than coffee. Coffee contains dozens of other compounds which is why most people will notice a greater effect on their heart rate and feel more jittery from a caffeine pill, than from drinking a cup of coffee with an equal amount of caffeine.

If you have the habit of using a stimulant before your workouts, and you exercise in the evening, wean yourself off of them. If you get better sleep, you might not be so tired before your evening workout.

Diseases

Cushing’s syndrome, Addison’s disease, adrenal insufficiency, and adrenal fatigue cause abnormal cortisol rhythms and are all associated with disrupted sleep. Nutrition, supplementation, and the right type of exercise play roles in mitigating the negative effects of too much or too little cortisol. You can work your way toward a more normal cortisol rhythm, and resilience to stress, but it takes months, sometimes years. Patience and persistence.

Common Sleep-Related Questions

Whenever I talk to someone about changing their sleep habits, I’m often asked the following questions. Since they weren’t specifically addressed above, I’ll briefly cover them here. Of course, you can continue the conversation in the VIGORESS (ladies) or VIGOR (gentlemen) Facebook groups.

Can I make up for my sleep debt during the week by sleeping in on the weekends?

No. According to the research, you need to be consistent with your sleep. Sleeping in a couple days per week won’t resolve the problems associated with your sleep debt from the other nights.

Is there anything else I can do to improve the quality of my sleep?

Other than what’s covered above, I’d recommend eating dinner a few hours before bedtime. Insulin levels should be back to baseline by then, allowing you to fall asleep faster.

I would also encourage you to block blue light, as exposure to blue light interferes with melatonin production. Many smartphones and laptops now have settings that allow you to shut off the blue light at night. It changes the color of the screen, but it’s worth it so you don’t sacrifice sleep.

I also recommend getting a pair of blue light-blocking glasses, if you tend to watch TV at night. I use a pair of Felix Gray glasses right now, but also have a pair of Gunnar’s.

One other tip. Make your room as dark as possible. No night lights, or status lights shining from your electronic devices. Your skin has sensors that pick up on light, even when your eyes are closed.

I have kids. How do I get more sleep when they’re up so late?

A teenager who goes to bed at 9 pm and wakes up at 6 am gets 10 hours of sleep. That’s the recommended amount in the table above.

Vanessa and I felt it was important to lead by example for our kids, so we went to bed at 9 pm, as did Jacob and Brodrick. There was no other option. We turned the house off at 9:00. If your kids are up too late to get enough sleep, that’s on you as the parent.

I also realize some kids’ are in sports practice past 9 pm. Do what you can to minimize the late nights, as their brains and bodies are in the middles of an important growth period. They need sleep.

Sleep Like a Boss

Laugh and the world laughs with you, snore and you sleep alone.

– Anthony Burgess

2555. That’s the number of hours, at a minimum, you should sleep each year as an adult. Just as a plane can end up miles from its destination by flying just a degree or two off from its course, you can end up far from healthy and fit by sacrificing just a little bit of sleep, night after night.

A year of falling 30 minutes short each night is 182.5 hours. More than an entire week of lost sleep.

If you got to the end of this long article, and didn’t fall asleep, congrats. My goal isn’t to just write something that’s interesting to read, though.

I wrote this to challenge you to take your sleep more seriously. You can always make money back. You can almost always find time to watch another show, or post a status update on social media. But you can never get back your time.

The hours you lose from sacrificing sleep are gone forever. Starting tonight, stop going further into debt, and make the most of the nights ahead of you. Sleep well.

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