CrossFit South Rockland

Monday, May 2, 2016

Heart Rate Variability and Sleep: How we are wired to sleep, part 3

Well kids, our time together is almost over. This is the third and final blog about how we are wired to sleep, what happens when things go wrong, and what steps you can take to fight back. I hope you have already learned some useful information, put it to use, and that those of you who need the help have tried out the sleep remedy on
For today, I’d like to start by summarizing the two major sleep regulating pathways that we have discussed so far, and talk a bit more about how to use those principles along with some additional techniques and tools to help you get higher quality sleep. Then, I’ll finish off by discussing the practical application of your new knowledge along with how to leverage a few new tools beyond our sleep remedy . Also, I’ll do my best to not overload you with unnecessary medical-science jargon.
So let’s get started! If you haven’t already, be sure to check out the two previous posts in this series. In part onewe focused on the melatonin pathway (sleep initiation), and part two we talked about the role of GABA (sleep maintenance). These two processes both need to be optimized to get good sleep, and that is why our sleep remedy focuses on only these two pathways. There are other ways to “create” sleep, but as we’ve talked about in the past; nothing leads to better sleep than optimizing the normal physiology that dictates sleep.
If you’ll remember, the production of melatonin triggers some changes to neurotransmitters, and decreases the production of stress hormones. Equally important, the increase of GABA in the brain leads to that pre-sleep groggy bliss that we experience, and keeps our environment from undoing all of the good stuff that melatonin production kicked off. It’s easy to understand why both of those pathways have to be active, but let’s talk about what an imbalance in these processes can cause, and how to avoid such an imbalance before it robs you of good, restorative sleep.
If you set up your light regulation well (i.e.- decrease blue light in your eyes, three to four hours before bed) you’ll very likely secrete an adequate amount of melatonin—as long as there are not interfering nutritional deficiencies: great first step. But, if you are still working at your computer up until 10 minutes before bedtime —even with your fancy new blue light blocking glasses —you’re ignoring the equally important GABA effect. The actions of melatonin may have produced plenty of GABA, but GABA can’t do its job in the best way it knows how when you continue to stimulate your brain and body. GABA is present, and decreasing the action potential of your neurons, but “wake promoting neurotransmitters” (See part one blog) are overcoming GABA’s effect.
These same neurotransmitters are likely what wakes you up in the middle of the night, and if this is the only time you have difficulty sleeping, that is the time I would recommend using our sleep remedy—instead of using it right before bedtime. Lack of melatonin production (one reason it’s very important not to overdose on melatonin like most supplements do) also allows adrenal stress hormones to be produced and decrease of GABA production. So, if you fall asleep easily, but wake up in the middle of the night, it is still likely caused by the same two pathways we’ve been focused on optimizing to initiate sleep.  If you are using our sleep remedy to help with your sleep, I recommend pre-mixing the drink (with less water if middle of the night urination is a problem for you) and drinking it when you wake up, then lay back, relax, meditate, breathe etc. Let yourself fall back asleep. Don’t “try” to go back to sleep. As always, don’t look at the clock, it doesn’t matter. You’ll wake up when your alarm goes off.
We know this by studying sleeping brains. When we put electrodes all over somebody’s skull, these electrodes can sense areas of the brain where a lot of neurons are firing at the same time (brain waves). This tells us which brain regions are most active, and by knowing which behaviors and activities are associated with various brain regions, we can analyze whether the sleeping brain waves are consistent with optimal sleep. Combined with a few other measurements, we create a graph called a hypnogram or hypnograph, and the visual information on these graphs tell us if you have optimal “sleep architecture”. These represent the various “stages” of sleep. All pathways must be working in unison in order for you brain data to produce an optimal hypnogram.
Of course, that’s not super practical—unless you have some pretty elaborate equipment, and a few sleep scientists in your home. Many of you use sleep aps on your smartphones, and many of you use wearable devices (like jawbone, fitbit, readiband etc.) to measure sleep quality. These are loosely coupled to sleep architecture, but since they are only measuring how much you are moving around, they aren’t exact. These devices are great for tracking sleep duration, and a reasonable approximation of sleep quality, but at the end of the day, you could get the same data by just laying completely still and not sleeping at all.
A more useful tool is a concept known as heart-rate variability monitoring. It’s outside the scope of this blog to explain all of the science behind these devices, but here is the basic concept; several variables affect how fast your heart beats [hormones, sympathetic tone, the heart’s built in pacer neurons (AV/SA nodes), etc.] Since you don’t have to think about contracting your heart muscles, we say that this is an “autonomic” function = automatic. The autonomic nervous system controls things we aren’t thinking about—heart rate, digestion, breathing rate, sweating etc. It is divided into two branches: “Sympathetic” = fight or flight (adrenaline) and “Parasympathetic” = rest and digest.
You could probably guess that the sympathetic nervous system increases heart rate. So, the parasympathetic should do the opposite, and indeed it does. If your autonomic nervous system is balanced, sometimes your heart rate will be slowed by the parasympathetic, and sometimes it will be accelerated by the sympathetic. This change—beat to beat—we call heart rate variability. If you are stressed out, anxious, or sleep deprived the sympathetic nervous system dominates and therefore reduces your heart rate variability (HRV). So, if you are sleep deprived you will have a low HRV, and that tells us that you are not in optimal health.
As luck would have it, some really smart people have invented products to help you train your heart rate variability (HRVT), and you can find these by putting “HRVT” into google, and read until you are sleepy (wearing blue-blockers if this is in the evening!). These are devices that measure HRV and recommend techniques that help you improve your HRV. While these training techniques can help you mitigate your poor HRV, they are mainly helping you mitigate against sub-optimal lifestyle choices—with sleep deprivation being one of the biggest. In fact, a fire-fighter just emailed me last week about his HRVT. He had been training for multiple months with a device, but after an initial rapid improvement he had plateaued in his score for multiple months. After taking our sleep product for one night, his HRVT score jumped by 20 points, and has stayed there. That is a HUGE improvement!!! In his case it was about a 40% improvement. So there! Sleep is KING!!! homer-simpson-on-nike-logo
Please review the tips from the first and second blog posts in this series and further incorporate some sort of tracking program to help optimize your time asleep, and the quality of that sleep. Something as simple as a pen and paper sleep log will help, but wearable devices, and HRVT are considerable improvements over writing down your approximate sleep time.
In my fantasy world I imagine everyone prioritizing sleep as number one, and building their lives around sleep. However, I am a realist. I recognize that sleep time and duration are often driven by work, kids, traffic, etc. But that’s no excuse not to optimize to the extent that your reality allows. The rest can be mitigated by leveraging our sleep remedy, taking naps, reduced/smart use of stimulants, eating a low inflammation diet, biofeedback, breathing techniques, meditation, HRVT and the like. All you can do is all you can do, but I promise—if you give it your best—all you can do will be enough!
As Porky Pig says; that’s all folks! But, don’t fear. This is just one blog series. We’ve covered a lot of ground in three blogs, and have only begun to scratch the surface. You’ll be seeing many more guest blogs from me, and many blogs populating my site. There is so much to cover about sleep, that I suspect I will have plenty of material to keep me busy for at least a few years. I hope you have found value in spending your time reading these first few blogs. I feel sincerely honored that you have invested your time in reading this information, and I thank you from the bottom of my heart. My passion is to get people excited about the value of sleep, and the use of sleep as one of the biggest bats in your performance enhancing bag of bad-assery. Keep an eye out, check out our sleep remedy, give us some feedback, and Get Some Sleep!

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