Minding the Borderlands

Mark Koester (@markwkoester) on the art of travel and technology

Heart Rate Variability: Science and Advanced Concepts for Understanding a Key Health Indicator

Ever wondered how stressed you are? Heart Rate Variability (HRV) is one practical way to objectively quantify your stress and health. While some amount of stress can be good, being in a constant, long-term state of stress can be very bad for our bodies and minds. HRV helps you objectively understand the state of your body and what factors trigger a stress response in you.

As a long-time biohacker and self-tracker, HRV has become one of my favorite biomarkers to track. It allows me to understand my overall state of stress on a day-to-day scale as well as contextualize what’s affecting my stress. It’s even something I can improve.

Quite simply: By measuring your HRV and capturing contextual factors like sleep, exercise, lifestyle stress, drinking, etc. you can understand your physiological stress.

What is Heart Rate Variability? Unlike Heart Rate (HR), which is the average number of beats of your heart in a minute, HRV is measuring the variance of intervals between heart beats. You can then use your calculated HRV to know if your heart rate is showing higher or lower variability in the moment and in comparison to your baseline average (typically last 7 days). Somewhat counterintuitively, lower variability is a sign of an increase in stress and activation of your sympathetic nervous system, and higher variability is a sign of being a state of rest and activation of your parasympathetic nervous system.

Your body is a complex system, and it deploys a number of systems to keep you alive and responds to its environment and internal states. Its goal is homeostasis or a kind of living balance. In order to maintain homeostasis and stay alive, your body responds to different situations through its different cells, organs, and organ systems. One of the most important is your nervous system, which transmits to different parts of the body to control actions.

In terms of the science that backs up HRV as a valuable biomarker it all comes down to how HRV acts as a proxy to a subset of your nervous system called Automatic Nervous System (ANS) and its two main branches, the Sympathetic Nervous System (SNS) and Parasympathetic Nervous System (PSNS). In order to better understand HRV and how stress works, we need to understand how HRV relates to your ANS.

In this post, which is a continuation of a previous post on HRV as a biomarker and how to track your HRV, we will be looking at Heart Rate Variability from a more scientific angle. Specifically, in order to understand our HRV scores and what factors affect our HRV, we need to understand how our nervous system acts through these two different subsystems. One of the main reasons HRV is such a key health indicator or biomarker is its ability non-invasively to tell us about the state of our automatic nervous system. For example, are we in a state of so-called “rest and digest” or in a mode of “fight or flight”?

Let’s dig in.

Common Sense Money Management: What Are Your First Principles of Personal Finance?

The basics of money and money management seem undeniable: spend less than you earn, avoid debt, save, and invest in a diversified, low cost portfolio.

How we behave with our money can be the difference between a successful, happy and stress-free life and an unsuccessful, unhappy and stressed one. Whether we like it or not, money matters.

Unfortunately personal finance can be a real struggle for many people and too many people let so-called “experts” manage their money, instead of spending a bit of time to first learn and make their own informed money decisions; and second to develop reliable instincts and habits for long-term financial success.

In my opinion, everyone should learn about money and understand how to budget, save and invest. The basics are not that complicated really. It’s consistent actions that are harder, and without consistent actions, you miss out on what Einstein allegedly called the most powerful force in the universe: compound interest.

In this three-part series on personal finance tracking, we will be looking at the basics of good financial behavior, how to track your finances, and how to come up with goals for saving and investing.

I’m no financial expert nor genius on money, but I have managed to create a life I love; a life where I save much more than I spend and invest it in ways that create returns. Good financial “ hygiene” and some tried-and-true investment strategies have enabled me to spend my time and money on the activities and things I truly enjoy without stressing out about money all the time too.

In this first part, I’ll share a few of the things I’ve learned about personal finance and money management. I call these “first principles,” and I think having simple go-to rules is a key part of being money smart. These are mine, and some of yours might be the same or the they might vary.

An Experiment in Mood Tracking: How I Tracked My Mood and What I Learned

Can we and should we track our moods? And if we could track our moods what would we learn?

For the last couple months, I’ve been running an experiment in mood tracking. For two separate two-week periods, I recorded my mood score five or six times per day by selecting a variable smiling, frowning or neutral face. I logged my mood a total of 134 times.

What were the results of my mood tracking data? Am I moody? Not really. On average, my mood has been either “ok” or “good.” There were a few instances of a neutral mood (I’m not a morning person), and a couple outliers where I was very happy. As life happens, on one occasion, I was “not ok.”

In this post, I’d like to share how I tracked my mood and some of the lessons I learned through this experiment.

How to Track Your Workouts: Become Data-Driven in Your Physical Fitness, Health and Performance

Wouldn’t it be awesome if you could capture and track all of your physical fitness and workout sessions?

Having a log of your workouts is a great addition to your fitness routines. Tracking workouts helps you stay motivated, see improvements, stay organized and on target, and watch your fitness story over time. With all the wearables, smart watches, and apps out there, it’s easier and easier to track your fitness and health.

Increasingly we can use this tracking data to understand our health and optimize our fitness too. I like to call this becoming “data-driven” about your life.

There are a lot of reasons and benefits to tracking your workouts. In “Why Track Your Workouts?,” I summarized it as: accountability, honesty, purpose, measurements, a summary of progress and health data.

Whether you are a self-tracking, data freak (like me) or not, tracking your workouts is one of the most beneficial data points to collect. Like tracking your heart rate, heart rate variability and sleep, I believe that anyone serious about their health and fitness should track and log their workouts.

There are a few aspects to tracking your workouts. First, the actual tracking of the event of your workouts; second, the aggregate logs of your complete training and the cumulative results; and, third, what you do and optimize with that data.

In this post, we will look at how to track your workouts in two key ways: logging and tracking. In the first part, we will look at the key data aspects to logging your workouts. At its most basic, when you log or track a workout you should be capturing when you did it, what you did and your key achievement.

In the second part, we will look at various apps, wearables and technologies to help you track, classify, and understand your workouts. With wearables, smart phones and even dedicated sensors, we can capture an array of data that wasn’t possible before. I’ll try and sort through all the options to provide you a good starting point on tracking your fitness.

Finally, we will conclude with what tracking your fitness and workouts can do. Namely, tracking data provide the ingredients to become data-driven. Using this personal fitness data, you can optimize your fitness plan for your goals and improve your health and performance outcomes.

Biomarkers: What Are They? Why They Matter? And How to Use Them to Improve Our Health?

When it comes to making improvements in your life, it helps to have some indicator of how you are doing. This is especially true when it comes to your health and wellness but it can apply to anything in our life.

When you think about indicators of your health and wellness, we use the term “biomarker,” which is short for biological marker and in its simplest definition stands for anything measurable that can indicate something about our health.

Alternatively in other contexts like biology (and outside the scope of this article), the term “biomarker” refers to substances that indicates something is alive or living organism. For our purposes, we are looking at biomarkers as indicators of either health or disease.

Biomarkers are in many ways the key to understanding our health, since biomarkers act as an indicator of the presence (or absence) underlying disease states. On an individual level, they also act as benchmark to one’s optimal health but also as a way to measure the effectiveness of a new drug or therapy.

Here are a few examples of biomarkers: LDL Cholesterol, Blood Pressure, Heart Rate Variability (HRV), Vital Capacity, VO2 Max, etc. Each of these can be used to understand your health status and predict risk of certain diseases.

While many biomarkers have been found and are well-researched and documented, biomarker discovery remains an active field in medicine and pharmaceutical industry since blood tests and biomarkers can serve as intermediate markers of a disease in clinical trials and help understand if a drug (or drug target) is effectively treating that disease.

In this on-going series of posts on blood tracking and biomarkers, we are looking at how blood tests and other biomarker data can be use to to help self-trackers and people in general understand their health. In the first post we looked at Benefits of Blood Testing and, in the second, we looked a project created to curate and catalogue the most common blood tests and biomarkers.

In this post, I want to take a step back and try to better define what are biomarkers and understand why they are so important. Specifically why are biomarkers the key both to the medical field and to us as individual humans trying to live well. While the stated goal is to live longer, healthier and more productive lives, I also simply want to have indicators of where I am on the health journey too. Finally, we will conclude by looking at how biomarkers in general and health tracking can be integrated in order to use them as a reliable feedback loop. The goal of health tracking with biomarkers isn’t just to collect data (health or otherwise), but to engage with those health metrics so it informs our decisions and leads to appropriate changes. Hopefully we can better understand what are biomarkers and how to leverage them in your own data-driven health journeys.

Biomarkers: Complete List of Most Common Biomarkers and Blood Tests (and Some Lessons Learned)

Ever wondered about those codes in your blood tests? Or ever asked yourself why are you getting these blood tests and not others? Or even gone one step further to ponder: Which blood tests should I get?

After spending a couple years tracking my life and health, I’ve become increasingly focused on the value of blood testing and blood tracking. There are a ton of positive reasons for regular blood testing.

Unfortunately, it’s a confusing space. In studying and thinking about my blood lab results, I struggled to even find a clear single source of information about biomarkers and blood tests today. There are a several sites sharing this blood info, but it’s scattered and misleading. Personally, I have read and reviewed over 400+ pages of articles and research on blood testing as well as a few books too.

For the sake of myself, data analysis and future comparisons, I’ve combined all of this to create my own “awesome” list of biomarkers, blood tests, blood testing companies, and biomarker and blood testing tools and technologies. With the goal of providing both an entry level source about blood biomarkers as well as a deeper “backend” on on-going information about blood testing, I’ve created an Open Source Blood Tests and Biomarker Database to help us understand our blood chemistry and our health based on our blood.

Check it out at: https://github.com/markwk/awesome-biomarkers or scroll to the bottom of the post for a summary.

NOTE: This list is a work-in-progress and meant to be collaborative effort, so feel free to post issues and help make improvements send them back for the community to share.

In this post, I want to share briefly on why I created this project, some lessons learned, and my conclusions. Finally, I’ve included the intro intro to biomarkers and blood testing at the end.

How to Track Your Mobility: Training for Performance and Injury Prevention

Your body is a machine you should know how to manage. For a racecar driver or motorbike racer, success or failure relies on keeping their machine in good working order and improving it. Your body is no different. You need to know how to access it, maintain it, and optimize it.

This is one of the interesting “unexpected” lessons I gained since I started running about two years ago. I played sports growing up, but looking back I never really trained at any previous phrase in my life. While in the end I reached several high points through my run training, including two full marathons and two half-marathons, interestingly I feel like my biggest learning was about my body and ongoing maintenance and respect you need to treat it with.

One of the key aspects of bodily maintenance and improvement is mobility. As author and proponent of mobility training Kelly Starrett likes to say, “All human beings should be able to perform basic maintenance on themselves.”

What is mobility? Mobility are exercise practices to ensure you are ready to perform correctly in your sport or physical activity. It means both being “ready” such that you won’t hurt yourself but also “ready” such that you can perform at your best. We might summarize mobility as better movement patterns, a stronger body to hold those positions and massage techniques to release tensions.

Mobility is a popular topic these days in nearly all areas of fitness, sports and performance. For running, in particular, mobility is touted as one of the key factors to running injury-free, which includes mobility, stability (i.e. strength) and deep tissue release.

You shouldn’t think about mobility as limited to “pre-hab,” meaning exercises to prevent injury. In fact, improved movement patterns and better stability strength can improve your performance. This means bigger gains in your lifts at the gyms and faster times at your races. Improved mobility translates to less mental strain since you become a well-oiled machine. Personally I’ve seen how important mobility work can be to allowing me to train hard and perform at my best.

Like running itself (and a lot of other aspects of my life), mobility is something I track and measure. I believe all goals, especially those in health and fitness, should be tracked. (SEE: Why Track Your Workouts?) You should be tracking your goals from two sides: Are you putting in the the necessary time for that pursuit? (commitment time tracking) and Are you making improvements in that pursuit? (progress tracking). In the case of mobility, you can track your mobility through assessments (i.e. exercises to gauge where you are and your progress) and through logging the time you send on your mobility workouts themselves. For me that’s the essence of being data-driven: tracking so you can reach a goal more effectively.

In this post, we are going to look at mobility training. We start by defining the importance of mobility for both injury prevention and improved performance. We will then look at a few tests to assess your mobility and, consider how expansive a topic it is, I’ll share a bunch of resources for further study. Finally, we will look at how to build a mobility routine and how to track it in terms of your weekly time commitment and in terms of your strengths and weaknesses.

Mood Tracking Apps on iOS: A Review of Apps for Logging Your Emotional Life

Here is my review of various apps and services you can use to track your mood on iOS or with your Apple Watch.

I wanted to try and track my mood. Since I’ve already tracked dozens of personal data points from my my health and my productivity to more obscure areas, I decided I want to explore one of the more active areas of self-quantification: mood tracking.

There are various psychological, philosophical and even practical challenges to measuring your moods. Firstly, one of the biggest problems is just now to define what is a mood? Secondarily, how best to “capture” and score that mood? I explored these questions and a few others in An Exploration of Mood Tracking: Can We Measure How We Feel?. My conclusion there was that moods are complex and most mood tracking is at best an abstraction. That said, for a self-tracker like me, mood tracking merited an experiment.

In this post, I want to share a review of the various mood tracking tools I tried, two of my favorites (MoodNotes and iMoodJournal) and my approach to mood tracking.

What Do Your Photos Say About You? Exploring Your Photo Metadata With PhotoStats App


That is roughly the number of photos that was taken by each smart phone user in 2017. That’s a lot of photos. That’s a lot of data.

But with this photo data, what insights and learnings are we able to get from our photos?

The photos on your mobile phone are one of the richest collections of data you have on yourself. If you regularly take photos with your phone (which most of us do), then your phone is collecting data on you.

Or to put it a more positive way, when you take photos, you also collect some additional data like where you were, what time and certain conditions at the time of the photo taking event.

Unfortunately, we aren’t leveraging our photo data to understand ourselves and our behaviors. While photo backup services might use our photo data, most actually strip the metadata on our photos and we lose it forever.

Fortunately there is a solution to start tracking, recording and leveraging your photo’s metadata. Using a new app called PhotoStats.io, you can are able to backup your photo metadata on your phone and, in turn, start leveraging it to understand a piece of data about your life.

In this post, I want to explore, visualize and start to understand my photo data. First, I want to share how to collect your metadata on your photos. We will get all of the metadata on your phone’s photos using an app called PhotoStats. Second, we will look into the information we can glean off that data as well as create a few simple visualizations and infographics. We will conclude with a bit of initial data exploration and visualization and some further areas for future research.