1 April 2016

Improving your Sleep - Part One - Understanding the mechanics

Like most people in this age I have struggled with getting a good night sleep. As a kid I always wanted to stay up later, thinking I was missing out on something cool by going to bed early. I would lay awake in bed for hours trying to sleep.

As a teenager I'd sleep in until 1pm on the weekends, usually with a headache, backache and with a bad case of the grumps. Half my weekend was lost to poor slumber and I was never rested.

As an adult I continued with poor sleep, still took hours to fall asleep due in part to my racing mind thinking about everything, and the habit formed over decades.

That was until I decided I'd had enough and began researching the science of sleep and how to improve its quality. This is what I discovered from experts in the field and my own trial and error.
The unfortunate and common knowledge is that caffeine helps to stay awake when sleepy. It has been indoctrinated to the populace and spurs the coffee and energy drink market. What isn't told to consumers is that the wakeful aspect of caffeine only lasts a short time and masks how tired you are rather than fixing the issue. As you consume more it makes you more tired and sluggish, and prevents you from getting better sleep.

Caffeine is a vicious cycle that only plummets you further down the rabbit hole. I've made further comments in this post about the process as part of the Feb 5 update. I strongly encourage you to remove caffeine from your diet if you truly want better sleep.

This article is going to be to long for a single post. If you wish to skip to the end and just read the recommendations without understanding why it works, please click here. I however recommend reading this in full as through understanding why something happens we are best positioned to take advantage of opportunities and avoid pitfalls.

Quality not Quantity
One of the biggest myths regarding sleep is the thought that you need 8 hours of it per day. Thinking of a good night's sleep in terms of duration is akin to thinking that drinking more dirty water will be better for you. It may quench your immediate thirst but it isn't healthy in the long term.

People only require 4 to 6 hours of sleep per night as long as it is of a good quality. But what does quality sleep look like? To answer that fully I need to run through the process of sleeping.

The Five Stages of Sleep
As the heading suggests there are five different levels of sleeping. Each stage is accompanied by a change in our brain waves. We don't need to understand the process or function of brain waves for these purposes. All we need to understand is that brain waves can be high and more intense, or lower and less intense. If they are higher intensity we fell more awake, when lower we sleep deeper. I'll include the brain wave names so if you're interest you can research them further.

When we have full wakefulness, we are at out peak brain wave intensity. Science has dubbed this as beta brain waves. In this state we can function as normal in whatever activities we choose (you have all chosen BJJ right?).

During stage 1 sleep we go into a lower brain wave state called alpha brain waves, along with the slightly lower theta brain waves. During this stage we are still very much awake. When you zone out or daydream you have hit stage 1 of sleep.

During this stage the body relaxes, our heart rate lowers and we breathe slower. The mind wafts in a state of relaxing creativity. Generally when we get a good massage we slip into this stage, which is just one reason of many why we feel better afterward.

Stage 2 sleep is when our brain waves incorporate two types called sleep spindles and K-complexes. Both of these aid in forming memories, along with other important functions such as learning what nerves control specific muscles. Changes in the frequency of K-complexes are often seen in people with restless legs or sleep apnoea. This stage is thought in some circles to represent the brain turning itself off or going into low power mode.

We can be easily woken from this state, and is the most common time to hear someone utter "I'm awake". I associate this stage with late night TV watching. You nod off but can still hear parts of the show you are viewing. You may miss 10 minutes before being woken by a sudden increase in volume like an explosion, or your head dropping off your supporting arm.

Stages 3 and 4 are closely related and in many sources they are combined. Our brains go into a period of very low activity called delta brain waves. The main difference in these two stages is the frequency of occurrence, stage 3 has delta waves above 20% of the time, and stage 4 above 50%.

This is when we are officially in deep sleep. During this time blood pressure, heart rate and respiration are at their lowest. Blood vessels dilate and the blood in our organs move into the muscles for nourishment and repairs. So just from this you can see deep sleep is critical to healing.

Finally, stage 5 is one most people are familiar with, that of REM sleep. This stage is associated with dreaming, and our brain waves are almost identical to that of being fully awake though it is much harder to be externally woken. Muscles are generally paralysed and heart rate, breathing and temperature are unregulated.

Sleep Cycle
During the night we don't just enter one of these stages are remain there. We go through the stages in a cycle that repeats on average 6 times per night. Typically the cycle goes through the stages as follows: 1, 2, 3, 4, 3, 2, REM, 2, 3, 4, 3, 2, REM...

But the stage order isn't the only factor, we also need to look at the duration of each stage, and that alters significantly. Take a few moments to study this graph and see if you can draw any conclusions.

As you may see, in the first cycle we enter deep sleep for a large period, and REM sleep is quite short. As the cycles continue, deep sleep lessens and REM sleep increases. By the end we no longer reach deep sleep and are primarily in REM. This is the perfect time to end sleep and begin our day. As mentioned earlier, our brain waves in REM are almost identical to being awake so it is a short hop to wakefulness. Secondly we are no longer benefiting from quality deep sleep and won't gain anything meaningful by remaining in bed.

Deep Sleep vs REM Sleep
These are the two most important stages of sleep. When we are sleep deprived we get headaches, drowsiness, nausea, concentration issues and muscle pains. Even after short periods of sleep deprivation our body sacrifices all other stages to get as much deep sleep as possible. This is one reason why the first 3 to 4 hours of sleep have the most time in stages 3 and 4. It also helps when sick as deep sleep is when disease fighting is the most active and efficient.

REM sleep is thought to be when we digest everything we learnt in the day, explaining why babies sleep a lot. As we naturally recover deep sleep first, it can be assumed that REM isn't as important for bodily function. The brain is wired to keep us alive as its primary function, so remaining alert and physically capable will be far more important than memory retention or dreams.

Quality vs Quantity round 2
So now we have sufficient knowledge to define quality sleep. Put simply, it is the ability to attain deep sleep and stay there for as long as required. We can't consciously do that but we can fix our systems to ensure the body does it for us. To do that we need to understand how the body regulates our sleep. This is a process the occurs over the entire day, and with the current form of society we are actually damaging that process.

The Body Clock
This is the internal system that regulates your body and sleep cycle. This entire 24 hour process is generally referred to as the circadian rhythm. This is an endogenous system meaning it's built-in and self sustained, however it is susceptible to external stimuli such as temperature, light and oxygen intake. There are a number of variables but what we're primarily interested in is: changes in body temperature; the release of hormones; and your activity levels.

Our body temperature changes throughout the day roughly between 36 and 38 degrees Celsius. When the body temperature rises we are more alert and brain waves are generally higher. When body temperature drops we feel more lethargic and lazy, and its a cue for the brain to lower our brain waves to stage 1 sleep.

Around mid-afternoon our bodies naturally drop in temperature. This is responsible for the afternoon slump. Ideally we would take a nap at this point but modern life doesn't allow for it. Most people just grab another coffee and power through. As body temperature rises again towards the early evening, we become more alert and active. This is when we are at peak performance, and the perfect time to do your physical training.

Issues arise when your body temperature rhythm is too flat. The brain doesn't get the right signals to wake and sleep so you have sleeping difficulties and you may never reach deep sleep. A correct rhythm will make us feel sleepy at the same time every night and wake us in the morning without an alarm.

Normally, this pattern will continue regardless of when you actually fall asleep. If you generally wake at 6am your body temperature will raise then as well. So regardless if you sleep at 11pm, 12:30am or 3am, your body temperature will rise at 6am and you will wake up.

This is the major cause of jet lag, physically you're in a different time zone but your body rhythm still follows its normal pattern. You can adjust but it may take a few weeks. When I was in LA for 10 days training with Eddie Bravo, I stayed awake until about 6am and woke around noon as this matched the normal time back home. Training was in the afternoon and evening so it worked out fine but if I needed to be somewhere in the morning I would have been tired and grumpy. Each day I felt the need to sleep earlier, until at the end of the trip I was falling asleep at around 2am. Upon returning to Australia it took another few days to get back into my routine and re-program my rhythm.

Body temperature is the most important aspect of this internal clock and greatly impacts your sleep and energy levels. So understanding how it can be damaged and repaired is critical to improving your sleep. We'll get to that but the next aspect we need to understand is hormonal.

This is primarily concerned with the release and suppression of the hormone melatonin, which is dependant on your exposure to sunlight. This hormone is created in the pineal gland and to a lesser extent the retina. This hormone puts you to sleep and restores energy during said sleep. When melatonin levels are high you will feel drowsy and lose energy.

When we're exposed to darkness, melatonin is released. The hormone levels increase from the instant sunlight stops hitting our eyes. Exposure to sunlight delays the drop in body temperature and keeps you awake for longer. Minimal sunlight allows a temperature drop and you feel sleepy. Being awake longer allows more time for sunlight to enter your eyes, delaying melatonin production. Sleeping for 9 hours and remaining tired is an indication of needing less sleep so you can let more sunlight in and return balance to your system.
Your points will change based on when you wake

So from this you can see how working in an office building isn't conducive to good sleeping habits. Unfortunately this is how many of us make a living, including me. I wake at around 6am, use artificial light to get ready, drive to work for about 15 minutes and spend the next 7.5 hours indoors. I then drive home, get ready for a few hours of training, again inside and away from sunlight, then go home after dark. Many people follow a similar pattern and have sleep issues. These issues can be addressed however.

Before we get to that, the last piece should be mentioned: your activity levels. The more cardio you get at night greatly impacts your body temperature rhythm. Exercise makes a quick rise in temperature, keeping you more alert. This creates a higher peak which gives more energy, but the important part for us is the following drop of temperature. As you are increasing temperature through exertion above your standard level, your body needs to drop more drastically to return to normal. This means it will stay lower for longer which promotes deeper sleep. We just need to be careful about the timing of this, as late night high intensity exercise will negatively impact sleep.

While we can certainly dig deeper into the mechanics at work here, the above is sufficient knowledge to move ahead and optimise our body clocks. I'll leave that for the next post. For now, please share your stories in the comments and work on getting more sunlight.

No comments:

Post a Comment