n=1: My Vagus Nerve on Chiropractic
Problems measuring HRV in practice
Refining HRV for meaningful use
My HRV Pre- and Post Adjustment I love measuring my own health data, and I especially enjoy measuring things that can be affected by the health of your brain and spine. One metric I'm paying a lot more attention to is Heart Rate Variability(HRV). HRV is a metric that's used to measure the function of a nerve called the Vagus Nerve. The Vagus nerve is unique because it stems from the brain and travels the length of your body to many of your key internal organs. This includes the heart, stomach, intestines, liver, spleen, and voice box. Over the past 10 years, studies have shown that a higher HRV measurement is associated with better outcomes in patients with heart disease, depression, and even cancer. If you want to know why, you can read my previous article on HRV, Vagus Nerve, and Cancer here: Research: Active Vagus Nerve Predicts Cancer Survival Regardless of Stage
Early Problems Measuring HRV in Practice Initially I wanted to measure HRV in practice as part of my chiropractic exam. After all, if chiropractic can change your nervous system, then you would want a tool that can measure the function of one the most important nerves in the entire body. The problem is that while HRV is a very powerful metric with a lot of validity, it can be a very fickle measurement when you don't take steps to control for confounding variables. Someone's HRV can change dramatically from measurement to measurement if they had a stressful day in the office, consumed too much coffee, or had a terrible night's sleep. It wasn't reliable enough for me to measure the effects of Structural Correction if I measured it on an occasional basis. So if we wanted to get good data, we had to change the way we measure.
Controlling Variables and Measuring Trends So if we know we have a valid measurement tool, then we just have to do our best to make sure we can make it more reliable. Instead of measuring HRV on random and arbitrary days, I decided to measure my HRV daily at a time where most variables can be accounted for. I measured it first thing in the morning when I got out of bed. Now we don't have to worry about a bad day in traffic or the affects of different chemical agents. With daily measurements, even the outlier measurements will be overcome by the law of averages. That way, we can see if an intervention really works by monitoring a trend of measurements improving rather than just reacting to a day to day change. But I don't think this is unique to HRV. I actually think that many of the measurements we care about could benefit from trends and establishing baselines. This includes blood pressure, cholesterol, blood sugar, and more. So many of these measurements can be subject to change based on lifestyle modification. Something as simple as sleeping better or a short term diet change can make an immense difference in a matter of weeks.
My HRV and Chiropractic One of the good things about experimenting on yourself is that you don't need to get outside permission to publish your own health data and stay HIPAA compliant. I ran a case study on myself recently. I'd been measuring my HRV over the course of a month so I can see how it responds to different types of exercise programs. In about 7 days, I established a pretty good baseline measurement of 95. Pretty darn good. I might see it drop as low as 56 or get as high as 130 depending on my sleep how hard I train, or various other factors, but my numbers consistently sat in the 90 -100 range. Then 2 weeks ago, I saw my measurements trend downwards where most of my measurements were in the 70's. A little unusual considering I haven't changed my lifestyle very much.
Trending back up
Trending back up
"There's too many illnesses like diabetes, heart disease, and arthritis that take years to build up before causing obvious signs of sickness. Waiting until symptoms arise can be disastrous for someone's health." While a drop in HRV isn't going to cause problems for me now, tomorrow, or maybe even for years, it's a recipe for lowered body resistance. We never know when the external forces working against our bodies will be too strong to overcome our body's defenses, but if we do our best to keep our internal resistance strong, then we can feel more confident in our ability to maintain longevity.