Want to know what Olympic athletes, Ironman winners, strongmen and the winner of Mr. Olympia have in common? They don’t work rotating night shifts.
My friend Danny has worked overnight shifts for years. She’s a nurse. Like, for 20 years she’s been doing this. She’s also a mother, so she has to get kids to school in the morning. Right about the time she should be getting into bed to catch up on her sleep, she has to get kids ready and get them out the door. When the kids were young, she had to be back to school within a couple of hours to pick them back up. Then back to school a couple of hours later to pick the older kids up. Then it was soccer, dance and any other activity they were involved in. Not to mention she had to find time for her workout somewhere in there. Not long after she gets home from running kids around from activities, her husband is getting home from his job and it is dinner time for the family. She has a very traditional marriage and loves to cook for them. After dinner comes homework, then a little later it’s bedtime for the kids. About the time she puts them down, it’s time for her to start her shift on the phones.
Danny does get sleep though. What she finds herself doing is catching sleep wherever she can throughout her day. But that’s not how sleep works. Gaining the healthy benefits from sleep requires 6-8 hours of downtime - in a row! She usually only gets about 3-4 hours sleep in a row.
Danny is a tough chick, but over the years this sleep schedule has taken a toll on her health. Thank god she has taken the time to add exercise to her daily task list, otherwise her medical issues could be much worse. Messing with your body's natural circadian rhythms is one of the worst things you can do for your health. We’ll talk more about these health complications below, but first let’s cover circadian rhythms.
Circadian Rhythms
We all have a built-in biological clock. It does more than you’d think. Among other things it controls:
wakefulness
sleep
metabolism
heart rate
blood pressure
body temp
etc.
Our biological clocks are set to a circadian rhythm that cycles every 24 hours. If we disrupt this cycle by just a smidge, like 1-3 hours, we'll feel it. Some of us feel it immediately. Others of us get a lag of several days, or even weeks. Throwing your body out of its normal rhythmic patterns is known to cause problems.
We know the part of your brain where circadian rhythms live. It's in your suprachiasmatic nucleus (SCN). That's in the hypothalamus. The hypothalamus seems to be fairly important to your health in that it regulates stuff like body temperature, fluids/electrolytes, hunger and hormone production. I'm not saying you couldn't get healthy without help from the hypothalamus; but if you were to fry the damn thing by screwing up your circadian rhythms hard and often, you might struggle a bit.
The other thing we know is your SCN is connected to the retina of your eye. If it is dark, the SCN tells your body to secrete melatonin and make you peacefully sleepy. If it's light, the SCN inhibits melatonin production. Hint: if you are having trouble sleeping please ponder on the "darkness" thing you just learned.
In the winter (assuming you live far from the equator), your SCN has developed a strange way of adapting to the longer periods of darkness. It produces melatonin in two stages. The first stage happens within a couple hours of sundown. Ever notice you get sleepy earlier in the winter? The second happens around 4 a.m. In the middle of these stages, there is a natural period of restful wakefulness. But there is a problem. In the developed world we don't go to bed earlier in the winter like our ancestors did. Instead of following our natural rhythms, most of us are just barely turning in right around our period of "restful wakefulness."By not turning in earlier when the first melatonin is released, it becomes more difficult to go to sleep.
Not getting enough sleep or enough of the right kinds of sleep throws us out of our natural circadian rhythm. This can be one of the reasons why (for some of us) our fitness goes to hell. It is also likely a contributing factor to weight gain, irritability (who doesn't get a little pissy about gaining weight?) and general lethargy. It can also be why so many of us get sick and depressed.
Therefore, here is one of the most important keys to attaining good health and fitness: Don’t let your circadian rhythms get too far out of whack. If they do, get back on track ASAP.
Problems with not getting enough high quality sleep
Memory problems. Lack of high quality sleep affects short term and long term memory. During deep sleep (REM) is where your brain forms memory and learning patterns.
Creativity and problem solving go out the window.
Emotional problems. Aren’t we hot tempered and moody enough? Lack of sleep is a leading contributor to anxiety and depression.
Weak immune system. Sleep is your frontline defense against infections that cause colds and flu.
Car accidents and accidents at work. Lack of sleep causes lack of focus.
Increased risk of diabetes. Lack of sleep causes your body to produce stress hormones like cortisol. Cortisol production increases blood sugar levels in the body. This can lead to type 2 diabetes.
Weight gain. Once again, stress hormones. Cortisol increases hunger and decreases satiety.
Decreases testosterone. Yep, stress hormones again. Cortisol is a catabolic hormone. This means it breaks down healthy tissue. It does this, in part, by suppressing testosterone and its effects. This lowers sex drive and vitality - in all people.
Increases risk of heart disease and stroke. Sleep deprivation increases inflammation. Inflammation is one of the leading causes of heart disease and stroke.
Lack of recovery - from workouts, life, ect.
The takeaway? Get on a sleep schedule. Get more high quality sleep. Shoot for 6-8 hours. You need more if you are active, stressed or older.
10 Tips for getting higher quality sleep after 40 (regulating circadian rhythm)
Go to sleep at the same time each night.
Get up at the same time each morning.
No caffeine after noon.
Have only 1 glass of wine in the evening. It has a calming effect. 2 glasses undo this calming effect.
Do not eat within 2 hours of bedtime.
Limit fluid intake close to bedtime.
Do not exercise within 2 hours of bedtime.
Dim the lights 1 hour before bedtime (dim amber colored lights are preferable to blue or white lights).
Develop a pre-sleep routine which decreases stress and activity (read books, listen to calming music).
Don’t lie in bed awake. If after 20 min you haven’t fallen to sleep, get up and do something calming, like reading or listening to calming music.
Humans can die faster of sleep deprivation than they can die of starvation. If you get less sleep than you need you’re just killing yourself slowly. He or she who wears 4 hours of sleep per night as some badge of honor, it’s time to re-think that. It’s time to take your health more seriously. Sleep deprivation (ie. slowly killing yourself) will wreak havoc with your body, mind and spirit. It’s unsustainable. If you pull it off short term, you’ll be lucky if you only experience temporary disruptions to your mood, memory or health. Long term sleep deprivation is dangerous and its side effects can be permanent.
Dieting and exercise don’t make any sense if you don’t get proper amounts of sleep. The fastest thing you can do to improve your health, like today, is to start getting enough high quality sleep!