Reminder: these are just my weekly numbers and they should not be seen as results. We can speak of those when the experiment concludes, after two months of data. Checking the numbers weekly will be interesting, but the actual results will only be visible at the finish line.

The (double-checked) baseline

For starters a quick recap of the baseline. These graphs are the standard to which the numbers of the following weeks will be compared.

More information about these graphs can be found in the post Heart coherence, the start.

Thirty-eight days of baseline data (24th of August - 30th of September) spread over two graphs, missing only the daily coherence measurement on the 30th of September. The top one shows my average coherence during the baseline sessions, as measured with the emWave pro. The bottom one is my overnight HRV value provided by my Circular Ring.

Average coherence:

The mean average coherence is 1.17 with a standard deviation (SD) of 0.23.

Average overnight HRV:

The mean average overnight HRV is 73.8 ms with an SD of 8.8 ms.

Thresholds:

For coherence the established threshold is 1.26 and for overnight HRV it is 78.5 ms.

The numbers

The graphs below contain the data from the experiment so far. They show the same information as the baseline ones, with two additions.

A purple line showing the practice average and a purple range band that shows the confidence interval (CI) of this average. These will change weekly when the new numbers are added to the analysis.

Average coherence:

The mean average coherence after the first month is 1.32 (up from 1.17) with an SD of 0.28.

Average overnight HRV:

The mean average overnight HRV after the first month is 73.2 ms (down from 73.8 ms) with an SD of 8.1 ms.

Confidence interval:

The CI band narrowed some more and the baseline coherence still falls outside of it. The experiment data and the baseline data are still distinguishable. Even when uncertainty in the baseline is taken into account, the practice average seems to be moving away from the baseline.1

A short explanation on the CI can be found in Heart coherence, the start.

Off-protocol measurements:

Last week there was one off-protocol measurement, but with a sidenote.

The 29th of October is the second flag due to artefacts. Only this time the artefacts were only flagged by Claude and not by the emWave pro app. Further investigation showed it was a false positive caused by a large breathing swing, not noise. The rule used by Claude to detect artefacts marks this as off-protocol.

Like I said, I will not change anything during the experiment, so measurements like these will end up flagged, but I will comment when it happens. After the experiment, the rule will be adjusted.

Interpretation:

The average coherence seems to stay above the established threshold, but with an SD of 0.28 the spread seems to be widening slightly. Week 4 on its own has the highest average coherence yet and it was during a week where my routine was slightly disrupted and not for the better.

The average baseline coherence still falls outside of the CI (1.24 - 1.40), but the CI does not yet clear the threshold.

Overnight HRV has now dipped below the baseline value. It currently sits 0.6 ms below it. The CI (69.1 - 77.4) still includes the baseline average value, but no longer the 78.5 ms threshold. The spread has widened, but mostly due to one reading. Allow me to elaborate.

This week I had my worst overnight HRV reading from the whole experiment, including the baseline period. If it weren’t for this one measurement, there would have been no remarkable changes. What is my hypothesis on how this happened? The night before the reading I had a social dinner with about three drinks at a friend’s place. Both the dinner and the drinks were a bit later than I have had them so far, so I would attribute the low HRV to this.

What does the data show so far? Mind you, I went looking for the data because of a bad reading, so this is not an independent check. I have had five “three-drink evenings” so far and they average 58.8 ms the next morning against 74.4 ms after alcohol-free ones. Evenings with only one drink, during an early dinner, showed no effect.

This is barely a discovery since it is well established that alcohol suppresses HRV. It does tell me that my readings pick up what they ought to pick up.

Halfway now. Coherence has been running above baseline, but only slightly. HRV on the other hand has given no clear signal yet.

Adherence

The adherence grid below shows how well I stuck to the protocol. The top three rows are the most important. They specifically concern the baseline and practice sessions. These will be marked with a red cross when they have not been executed.

The rows below show how well I logged everything else in my app. These will be blank when they are not filled in.

Protocol adherence:

Complete

Logging adherence:

Missed three TM sessions between the 27th and the 29th of October.

What was going on

Last week I assisted at a driving course. Due to the distance to home, I slept at a friend’s place. The days were filled and more exhausting than usual (I guess that’s what instructing does to a person). An unexpected dinner with some unexpected alcohol (I do not always have a lot of character) has definitely taken a toll on my readings this week.

Since the week is not over yet and I still have some renovating to do, I can again say that it was quite a busy week.

Sidebar

With regards to the sidebar of last week I can now say that the S1 sessions are no longer consistent. This week the average of the morning sessions was lower than the previous weeks and the gap with the evening session was smaller.

So far I have only been talking about my primary metrics (average coherence and average overnight HRV). Since we are now halfway, I will shed some light on the secondary metrics.

Alongside the primary metrics I am also tracking nineteen secondary ones. Only one of them really moved. I am sorry for a rather boring paragraph, but it is the honest answer. The one that moved was self-rated morning stress. But this subjective rating works more as an event detector than an intervention detector. Every one of the high-stress mornings had an identifiable cause. I guess life might sometimes be too random to notice anything.

Worth noting that out of nineteen comparisons you would expect about one to look interesting by pure chance. This is reassuring in a way, since it suggests the numbers are not throwing up false patterns.

But this is just an early look at the secondary metrics. On to the second half of the experiment!

Reminder: these are just my weekly numbers and they should not be seen as results. We can speak of those when the experiment concludes, after two months of data. Checking the numbers weekly will be interesting, but the actual results will only be visible at the finish line.

The (double-checked) baseline

For starters a quick recap of the baseline. These graphs are the standard to which the numbers of the following weeks will be compared.

More information about these graphs can be found in the post Heart coherence, the start.

Thirty-eight days of baseline data (24th of August - 30th of September) spread over two graphs, missing only the daily coherence measurement on the 30th of September. The top one shows my average coherence during the baseline sessions, as measured with the emWave pro. The bottom one is my overnight HRV value provided by my Circular Ring.

Average coherence:

The mean average coherence is 1.17 with a standard deviation (SD) of 0.23.

Average overnight HRV:

The mean average overnight HRV is 73.8 ms with an SD of 8.8 ms.

Thresholds:

For coherence the established threshold is 1.26 and for overnight HRV it is 78.5 ms.

The numbers

The graphs below contain the data from the experiment. They show the same information as the baseline ones, with two additions.

A purple line showing the practice average and a purple range band that shows the confidence interval (CI) of this average. These will change weekly when the new numbers are added to the analysis.

Average coherence:

The mean average coherence so far is 1.30 (up from 1.17) with an SD of 0.26.

Average overnight HRV:

The mean average overnight HRV so far is 73.9 ms (near identical to 73.8 ms) with an SD of 5.6 ms.

Confidence interval:

The CI band narrowed some more and the baseline coherence still falls outside of it. The experiment data and the baseline data are still distinguishable.

A short explanation on the CI can be found in Heart coherence, the start.

Off-protocol measurements:

No off-protocol measurements this week.

Interpretation:

The average coherence still sits slightly above the established threshold, but with an SD of 0.26 you can clearly see the range of measurements widening. Week 3 on its own has the lowest average coherence yet and it contains the lowest reading yet (baseline period included) on the 22nd of October. Just like the single high reading from last week there is no specific explanation for it and the measurement was solid.

The average baseline coherence still falls outside of the CI (1.21 - 1.39), but the CI does not yet clear the threshold.

Overnight HRV seems to be returning to the baseline value. It currently only sits 0.1 ms above it. The CI (69.2 - 78.7) still includes the baseline average value and the 78.5 ms threshold. The spread is tightening though.

Three weeks in, the numbers are not really showing me clear results just yet.

Adherence

The adherence grid below shows how well I stuck to the protocol. The top three rows are the most important. They specifically concern the baseline and practice sessions. These will be marked with a red cross when they have not been executed.

The rows below show how well I logged everything else in my app. These will be blank when they are not filled in.

Protocol adherence:

Complete

Logging adherence:

Complete for this week

What was going on

Another rather busy week, but according to my log I remained calm. During the day I was mostly working on developing my coaching business (both in a practical and intellectual way) and I spent most of my nights attending webinars on different topics, from breathing to investing.

Sidebar

After three weeks there is something to be said about my practice sessions S1 (morning) and S2 (evening). This is exploratory, not a conclusion.

The morning sessions score consistently higher than the evening ones. The average for S1 is 5.10 with an SD of 0.56 and the average for S2 is 4.14 with an SD of 0.92. The gap between both averages is 0.96.

While the morning sessions were consistent throughout the first three weeks, the evening sessions improved meaningfully. They started out at 3.5 in the first week and have gone up to around 4.5 in the weeks after. This happened more as a step than a gradual climb, so I cannot say with certainty that it is because of training.

On to the last week before the halfway milestone!

Reminder: these are just my weekly numbers and they should not be seen as results. We can speak of those when the experiment concludes, after two months of data. Checking the numbers weekly will be interesting, but the actual results will only be visible at the finish line.

The (double-checked) baseline

For starters a quick recap of the baseline. These graphs are the standard to which the numbers of the following weeks will be compared.

More information about these graphs can be found in the post Heart coherence, the start.

Thirty-eight days of baseline data (24th of August - 30th of September) spread over two graphs, missing only the daily coherence measurement on the 30th of September. The top one shows my average coherence during the baseline sessions, as measured with the emWave pro. The bottom one is my overnight HRV value provided by my Circular Ring.

Average coherence:

The mean average coherence is 1.17 with a standard deviation (SD) of 0.23.

Average overnight HRV:

The mean average overnight HRV is 73.8 ms with an SD of 8.8 ms.

Thresholds:

For coherence the established threshold is 1.26 and for overnight HRV it is 78.5 ms.

The coherence threshold of 1.26 is identical to the one published in the protocol post. The HRV one is slightly lower than the 79.2 ms mentioned, making my experiment marginally easier.

The numbers

The graphs below contain the data from the experiment. They show the same information as the baseline ones, with two additions.

A purple line showing the practice average and a purple range band that shows the confidence interval (CI) of this average. These will change weekly when the new numbers are added to the analysis.

Average coherence:

The mean average coherence so far is 1.33 (up from 1.17) with an SD of 0.25.

Average overnight HRV:

The mean average overnight HRV so far is 74.2 ms (up from 73.8 ms) with an SD of 6.2 ms.

Confidence interval:

It was mentioned in last week’s post that the band would become smaller with every reading added and you can clearly see this happening. What is interesting is that you can now see the average baseline coherence falls outside of the CI. This means the experiment data and the baseline data are now distinguishable.

A short explanation on the CI can be found in Heart coherence, the start.

Off-protocol measurements:

One off-protocol measurement this week on the 15th of October. This one is due to artefacts1. When a session contains more than 5% of them, it is flagged as off-protocol. This week’s flagged session contained 5.02% artefacts.

Interpretation:

For the second week in a row now the average coherence sits (only slightly) above the established threshold. The SD went up from 0.20 to 0.25 though, meaning that the readings are more spread out. New for this week, as I just mentioned, is that the average baseline coherence now falls outside of the CI. This is progress, but still not a result. I want the CI to clear the threshold too.

The numbers for this week include a high reading on the 12th of October, as you can see on the top graph. Without this reading, the experiment and baseline data would not yet be distinguishable.

Overnight HRV is still a little bit higher than the baseline, but the threshold of 78.5 ms has not yet been crossed. Week 2 on its own actually sits below baseline, which is interesting, since it clearly shows how readings can differ from one week to another.

Success can only be measured at the end. About six more weeks to go :)

Adherence

The adherence grid below shows how well I stuck to the protocol. The top three rows are the most important. They specifically concern the baseline and practice sessions. These will be marked with a red cross when they have not been executed.

The rows below show how well I logged everything else in my app. These will be blank when they are not filled in.

Protocol adherence:

Complete

Logging adherence:

Complete for this week

What was going on

All in all it was a rather busy week, but my log clearly shows that I got calmer. Makes sense after last week’s events.

An interesting note on the artefacts of the 15th of October. I logged that I sneezed a couple of times during that session. This is a perfect example of what an artefact could be and it shows the usefulness of logging.

Erratum, 10 Oct: I used baseline values calculated on only part of the baseline period. The correct figures are marked in the text below, and the wording adapted where needed. I am double-checking the thresholds and will report on those next week!

Reminder: these are just my weekly numbers and they should not be seen as results. We can speak of those when the experiment concludes, after two months of data. Checking the numbers weekly will be interesting, but the actual results will only be visible at the finish line.

The baseline

For starters a quick recap of the baseline. These graphs are the standard to which the numbers of the following weeks will be compared.

More information about these graphs can be found in the post Heart coherence, the start.

Thirty-eight days of baseline data (24th of August - 30th of September) spread over two graphs, missing only the daily coherence measurement on the 30th of September. The top one shows my average coherence during the baseline sessions, as measured with the emWave pro. The bottom one is my overnight HRV value provided by my Circular Ring.

Average coherence:

The mean average coherence is 1.17 with a standard deviation (SD) of 0.22 0.23.

Average overnight HRV:

The mean average overnight HRV is 75 ms 73.8 ms with an SD of 8.7 ms 8.8 ms.

The numbers

The graphs below contain last week’s numbers. They show the same information as the baseline ones, with two additions.

A purple line showing the practice average and a purple range band that shows the confidence interval (CI) of this average. These will change weekly when the new numbers are added to the analysis.

Average coherence:

The mean average coherence so far is 1.31 (up from 1.17) with an SD of 0.20.

Average overnight HRV:

The mean average overnight HRV so far is 75.3 ms (up from 73.8 ms) with an SD of 6.9 ms.

Confidence interval:

At first sight it looks like the purple band can be directly compared to the teal band showing the SD from the baseline readings. This is however not the case!

The teal band shows one SD. It means that about two in three readings fall within this range and it shows us the typical morning. The purple band, on the other hand, shows the 95% CI1.

Currently there are only nine readings, which is not a lot. An average based on only a few values is not precise. The more numbers we add to the analysis, the smaller this purple band will become.

Worth noting that right now the baseline average still falls within the practice range CI. This means they are not yet distinguishable. As soon as the baseline average falls outside, we can start talking about a separation. This would be a progress signal, but not yet a success criterion.

Interpretation:

As mentioned earlier, we can hardly draw conclusions from the first nine days of an experiment. Yes, the average coherence is now just above the 1.26 threshold I fixed in the protocol post – as noted above, I am verifying this figure. If this holds over the coming weeks, until the end of the experiment, it is a nice start. HRV on the other hand only sits marginally above the baseline number.

With the CI integrated in the graphs, I will make it a bit harder on myself. I want to surpass the established thresholds, but I also want the CI to be higher than these thresholds to declare success.

Adherence

The adherence grid below shows how well I stuck to the protocol. The top three rows are the most important. They specifically concern the baseline and practice sessions. These will be marked with a red cross when they have not been executed.

The rows below show how well I logged everything else in my app. These will be blank when they are not filled in.

Protocol adherence:

Complete

Logging adherence:

Missing the evening form on the 4th of October

What was going on

Sadly, the past few days were anything but average. My grandfather passed away at the age of 94. Apart from the last few years, he was always in good health and determined to turn 100 one day. Since he will no longer be able to do so, I hereby officially declare I will take over this quest from him!

While the numbers of this week might seem “normal” or as expected, the events have taken a toll on me. It did not happen unexpectedly and it was a beautiful moment in its own right, but it nevertheless impacted my mental and physical state.

Requiescat in pace bompa…

This post will replace the one I would normally put out on Saturday (only for this week). Better to post the final baseline data now before starting than showing you two days of data on Saturday.

It will also serve as a first draft for the layout of my reporting. So if there are any remarks, just respond to this post or email me!

The protocol

The protocol has now been fixed as it has been published. The SHA-256 of the text is: 507d3626f13dd12d9286a4f45e212715e8ae176132e2c2c46dc68deb69f369c7.

Holy crap, what did I just read? You could consider those numbers and letters to be the fingerprint of the protocol text. If I were to change anything, this hash will no longer match.

Currently this does not yet allow anyone, besides me, to check the text. I will publish the protocol text as a plain file in the days to come, so everyone can verify whether the file matches the hash.

I have also archived the post on web.archive.org under the following link.

Baseline data: primary metrics

The same graphs I have shown in my last publication, but more polished. This time I will dive a bit deeper since this is the finalisation of my baseline period.

The period:

I ran the baseline measurements with the emWave pro from the 24th of August to the 30th of September. Thirty-eight days, of which thirty-seven have a baseline measured. Each dot you see on the graphs is the reading of a specific day, which you can see on the bottom. The dates marked at the bottom are always a Monday.

The graphs:

The top graph shows my average coherence during the baseline sessions, as measured with the emWave pro. The bottom graph is my overnight HRV value provided by my Circular Ring.

The legend:

I already mentioned the little green dots being readings linked to each morning’s baseline session. Let me explain the rest of the information on the graphs.

The X-axis represents the timeline and the Y-axis shows either the average coherence (top graph) or the HRV (Circular Ring, bottom graph). Whenever a green dot is circled, this means the conditions for the measurement were not standard1. The line connecting the dots is just there to show the trend in a more visual way. The dotted line shows the baseline mean, calculated from all the baseline measurements. This line will remain my “baseline” for the rest of the experiment.

Finally the green zone represents one standard deviation (SD) up or down from my baseline. It visualises the normal range of the day-to-day variation. The thresholds in the protocol are derived from the SD. Once an average value lands and stays outside of this range, it means something.

Baseline data: secondary metrics

The analysis of the secondary metrics has not been done yet. The logging app only covers the most important metrics and I still need to pull the data from various devices and apps. Posting them now would take us too far, but I will report on the analysis in a future publication.

I will now run you through the protocol for this experiment.

The logging app

Besides the coherence data, I also gathered my other baseline stats. All of these are logged in the app I mentioned in the publication, My tools. This also describes the different tools I use to provide the data.

Let me start with a word on the logging app and what it contains exactly. The first version is now finalised and will not be changed throughout the experiment. Excluding of course aesthetics if something were to really bother me. I can also no longer adapt previous days, except for an afterthought that will be timestamped.

The application contains the following sections, in order, followed by a brief description.

Morning:

This section contains a subjective part where I rate my sleep and feeling (spoilers: it is usually not that good, I am not good at waking up, remember?). It covers sleep quality, energy, mood and stress. The rest of that objective data comes from my Circular Ring, except for blood pressure. It also tracks whether I have a transcendental meditation session or not.

Baseline:

The data from my baseline session goes here. The section contains the time of day, average coherence score and mean heart rate. This input comes from the emWave pro.

S1:

The first coherence session of the day, straight after the baseline session. The time of day is noted, just like the protocol I use (emWave, ring or free pacer), the average coherence score and the breath pacer setting. Subjectively it asks whether I felt the shift after the session.

Sports:

Basic information about my sports sessions is tracked here, my Garmin does the rest. I note the type of session, the Rating of Perceived Exertion (RPE), training time and time of day.

Midday:

A subjective section where I write down the time of day, my energy, stress, mood and focus.

Evening:

Energy, stress and mood come back and then a summary of the day. Where I will sleep (home, Sweden, away), what kind of day it was (work, renovation, business or quiet) and life load (light, normal or heavy). Whether I did any breathwork outside of the protocol and, if so, for how long. And finally it keeps track of alcohol consumption, caffeine after 1400 and if anything else was off.

S2:

The exact same as S1.

Every section also has a “free text” part for any remarks.

The preparation

The experiment will start in October, but with the baseline data I needed, it has already been running since August. Without this data I would have nothing to compare against. So what did this preparation look like?

The logging app:

I just described the logging app; now I will tell you how I have used it so far. The section names already give it away a little, but morning could be anywhere from waking up to around 1300. At least for me.

When do I do the logging?

Morning: The subjective part is filled in right after waking up. When I still feel awful from a good night’s rest. The data from my ring and my blood pressure is filled in right after I have done my baseline session.

Baseline: The baseline session is logged right after it has been recorded.

S1: No coherence session done yet, but I will log them straight after recording.

Sports: No specific time to log this one. I do it the same day when I think about it.

Midday: The midday section is logged around 1200 before lunch.

Evening: The evening section is logged around 2100, after dinner.

S2: Same as S1.

The emWave pro app:

To measure my baseline coherence I use the emWave pro app every morning for five minutes after waking up, drinking some water, having a pee and finally weighing myself.

What does a baseline session look like?

First I plug in the USB module and attach the sensor to my ear. I start a session just to see if it actually starts recording. Otherwise I might have to clean the sensor or check the connection. I make sure the lights on the USB module are not visible and the audio feedback is off. Then I start the (five minute) session, turn on a neutral screensaver and set a timer for five minutes. I sit still behind my laptop in a neutral position, both feet on the ground and try not to focus on anything in particular, especially not my breathing. When the five minutes are over, I remove the sensor and log the session.

Except for testing, I do not run any other emWave sessions. The coherence training starts in October, so I will not be messing around with it before that time.

Below you can find the outcome of my baseline practice up until now. The graph shows my primary outcomes which I will expand upon a bit further ahead. I started using the app on the 17th of August. The 24th of August was the first day I started logging my baseline coherence sessions.

An overview of the baseline data from the 24th of August to the 24th of September.

After analysis of the baseline (24 Aug - 21 Sep), resting coherence seemed to be steadily drifting upward. This would have meant that my baseline increased on its own, just by running the measurements, and the increase was big enough to be significant. Adding the extra days (22 - 24 Sep) to the analysis showed that it was just a high week and not a trend. Before kicking off, all data will be integrated.

The experiment

During the experiment I will continue doing what I did during the preparation phase; also check my previous post, The confounders. On top of all this, I will add two five-minute coherence sessions with the emWave pro per day. A complete day will require both sessions to be logged. Why five minutes and why two sessions? I like it when a habit does not take up too much time, so five minutes should work without feeling like a chore. Two sessions is also not excessive, so I am sure I will do them daily and not forget about them when life happens. This is also the practice Rollin McCraty (PhD, director of research at the HeartMath Institute that sells the biofeedback devices) uses, as I mentioned last week in the Heart coherence publication.

When will I run the sessions?

The first session will take place in the morning, right after finishing the baseline session, measuring my BP and logging my data. My transcendental meditation will take place after this session. The second one will be run right before going to bed; the last thing I do. Since this will not be at the exact same moment every day, the time will be logged with the session. I chose these moments because it makes the sessions fit into my morning and evening routine, making it easier to turn them into a habit.

How long will I run them for?

I was initially planning on running every experiment for only one month, but it might not be enough to see clear results. That is why I have decided to run this experiment for two months, with an intermediate evaluation after one month. This evaluation is just a progress report and will have no effect on the experiment, it will keep on running. After this period I will continue testing my baseline for another month to see if my coherence reverts to baseline. Since this will be done in December, the outcome of this “withdrawal” phase could be affected by multiple other factors. It is the darkest month of the year, a holiday period, some alcohol might be involved, etc. Plenty of reasons for my routines to be disrupted. Nevertheless I will stick to them as well as I can and log everything out of the ordinary. There are three weeks before the start of the holiday period, these should not be affected as much.

During this last month I can also prepare for the next experiment. So the rest of this year will focus on heart coherence.

What will the sessions look like?

As mentioned, the sessions will take five minutes. They will be run at the lowest challenge level1. This does not influence the calculation of the average coherence score, so it is just to be coherent throughout the experiment. I will use the breath pacer in the app, which will have me breathe six breaths a minute. During the sessions I will use the device’s feedback since I will be aiming for a high average coherence.

Specific confounders

But what if I end up sick? As long as it remains possible, I will stick to the experiment. The illness will be logged and taken into account during the analysis. In case of a long interruption (two weeks or more) I will extend the experiment or restart it.

Caffeine should not be an issue. My first cup is always after my morning measurements and I stop drinking coffee in the afternoon. Any exceptions will be logged.

Alcohol will be the biggest confounder. I do not drink a lot or regularly, but it does happen. When I drink it will be logged, but the effects can last up to twenty-four hours. The analysis will take this into account.

The outcome

The experiment will look at primary and secondary outcomes. The primary ones are the ones I am aiming to improve with the experiment. The secondary ones can be considered as side effects, but they can be interesting nevertheless.

Primary outcomes:

I have defined two primary outcomes for the experiment. The average coherence score I get from my morning baseline sessions and the overnight HRV rating I get from my Circular Ring.

These are claimed to improve when practising coherence regularly, so that is what I will be testing.

Secondary outcomes:

The secondary outcomes are anything else I log that might be affected by the coherence practice. For these I will be looking at the following data:

• Anything coherence related that is not the average coherence score (achievement score, coherence ratio, within-session trend, peak frequency location, practice-session scores over time versus baseline-session scores)

• Sleep (total sleep time, sleep efficiency, time to fall asleep, wake episodes, stage distribution, sleep debt)

• The cardiovascular system (resting HR, overnight minimum HR, day-to-day HRV variability, BP, pulse)

• Respiration (overnight breathing rate, SpO2)

• Subjective feelings (morning grogginess, general feel, energy and stress)

• The body (weight, overnight skin temperature)

• Training (perceived exertion, CAROL power output, VO2max estimate)

Success criteria and numbers:

Ideally both primary outcomes see an increase against the full six-week baseline period as mentioned above. This would make the experiment a success. If only one of the outcomes sees the desired improvement it will be considered a partial success.

If any of the secondary outcomes are positive, it can be seen as a nice to have, but they will not have an effect on the successful outcome of the experiment. All of the items on this list are exploratory. If they increase, it is an interesting sidetrack to investigate at a later moment.

The secondary outcomes could however prevent the experiment from being a success. This will be the case if any of the metrics decline by more than twice their detectable change, measured over the full intervention period. This type of decline is big enough to matter rather than be noise.

The outcome will be determined by all logged data of the whole experiment period, even days that are not complete. All data matters and even not practising can have an effect. An analysis of only complete days will be made as well.

What are the numbers I will be looking at?

With a few more days to go before my baseline period ends, these numbers might shift slightly. On the 1st of October I will report the definite numbers. The method by which they are calculated remains the same.

My baseline average for coherence currently sits at 1.17, with a standard deviation (SD) of 0.22, and for HRV at 75 ms, with an SD of 8.7 ms. These numbers will be used in two comparisons. The first one will compare these numbers against the full experiment over the months October and November. The second one will compare them against only November. The learning curve will be steeper in the beginning and it should stabilise in the second month.

For the average coherence there is a real effect if it reads over 1.26 for the whole experiment and over 1.28 for the month of November. These are 8% and 9% improvements.

For the overnight HRV there is a real effect if it reads over 79.2 ms in the first case and over 80 ms in the second. These are 6% and 7% improvements.

These values are derived from my baseline variability. This means the change during the experiment has to exceed normal day-to-day variation, calculated from the standard deviation.

Experiment structure:

The experiment is structured in an A-B-A fashion. “A” being baseline establishment and reverting to baseline and “B” being the intervention. With regards to this structure there are three possible outcomes:

• Primary outcome is successful and rises during the experiment; it falls again during the withdrawal period.

• Primary outcome is successful and rises during the experiment; it stays elevated during the withdrawal period.

• Primary outcome does not change during the experiment; no point in having a withdrawal period.

The first option would be the strongest evidence of the effect of the practice. The second one could mean there is a lasting trait change, but it could also have to do with drift or seasonality. The final one would mean the practice has no effect (on me).

Final reminder:

Important to keep in mind that there might be a ceiling problem here. I am already trained in breathwork and meditation, so no effect does not necessarily mean these interventions do not work. They might just have no effect on my already trained state.

What is coherence?

As I mentioned last week, Heart Rate Variability (HRV) represents the variation in intervals between heartbeats. Coherence simply means a smooth, rhythmic variation. This variation can be seen on the top part of the reading in the emWave pro app. On the bottom left you will see the coherence over time with three colour-coded zones that change depending on the challenge level you use within the program. Green means you are in a coherent state and red is of course the opposite, while blue is in between. With the coherence over time your coherence score is calculated. Finally on the bottom right you have the spectrum average where you can see the average of the different frequency components of the heart rhythm.

Since a picture speaks more than a thousand words I will show you what coherence looks like.

This first print screen was taken from one of my baseline sessions with the HeartMath emWave pro. These are the sessions I have been running daily since mid-August to establish my baseline coherence before starting the experiment in October.

As you can see on the upper part of the reading, the line representing my heart rate (HR) over time is quite jagged and irregular. The bottom left shows my coherence over time and it is mostly in the blue (meh) and red (oh no!) zones apart from one peak in the green (good job!) zone. The bottom right shows the frequency spectrum during the measurement. Here it is between 0 and 0.5 Hz with a big peak below 0.1 Hz.

The second print screen was taken from one of my best sessions. Not a baseline session, since I do not focus on anything during those, but a focused breathing session.

Here you can clearly see a fluent harmonious line, almost like a sine wave. My coherence over time (bottom left) is exclusively in the green (good job!) zone. On the frequency spectrum (bottom right) I have a big peak at 0.1 Hz.

How does it work and why do I want it?

Breathing plays a big part and can directly influence heart coherence. What is the mechanism behind this? I will try to explain it in an easy manner.

The heart and lungs are both connected through the vagus nerve, which is responsible for the parasympathetic nervous system. This nervous system is one part of the autonomic nervous system; the other one being the sympathetic nervous system. They are often described as the fight or flight (sympathetic) and the rest and digest (parasympathetic) systems. Through this connection, breathing can directly influence the HR.

This is where respiratory sinus arrhythmia (RSA) plays a part. Contrary to what was once thought, the heartbeat is not a stable rhythm that only changes when you become more (or less) active. Even at rest, the HR changes between every beat. As you can see on the image below:

• When you breathe in (blue sine wave going up), the heart starts beating faster (orange heartbeat graph with closer intervals). Breathing in inhibits the vagal outflow to the heart, allowing the HR to go up.

• When you breathe out (blue sine wave going down), the heart slows down (orange heartbeat graph with larger intervals). Breathing out resumes the vagal outflow and the HR can fall again.

Playing around with your breath has a direct influence on this. If you breathe out for longer, the heart has more time to slow down and your HR will drop. So your breathing pattern has a direct impact on your HR.

This has a few positive effects. Instead of an automatic gearbox, it gives you a semi-automatic gearbox. You have the option to shift gears whenever you feel like it or need it. This allows you to regulate your nervous system, useful for people dealing with chronic stress, for example. It can help reduce your blood pressure (BP), useful for people with hypertension. There is also evidence that it helps improve the BP regulation system.

Practising it regularly is also claimed to help increase your HRV. This is exactly one of those claims I want to test for myself!

How do I get it?

Breathing can help to get you in a coherent state, when you focus on it. For coherence a Breathing Rate (BR) of six breaths per minute is the reference. It means you complete a full breath cycle every ten seconds. Five seconds in, five seconds out. We can link this back to the emWave pro session images I described earlier.

The second emWave graph I showed was from me doing exactly this and it gave near perfect coherence. I mentioned 0.1 Hz in the What is coherence? section; now is the time to expand a little on that topic, since it relates directly to the breathing part. One of the frequencies that plays a part for the spectrum average is the BR. In this specific case the 0.1 Hz means 0.1 breath per second, or one breath per ten seconds (the BR mentioned in the previous paragraph). Adopting this rate gets you in a state of coherence, because BP also oscillates roughly every ten seconds. When the two frequencies match they amplify each other. This is the reason why my good session had a peak at 0.1 Hz and the baseline session did not.

So will I now try to keep that BR for the rest of my life? Unlikely. Breathing is still a mostly automatic system and most of the time I will not be paying attention to it. Being coherent is easy enough when you focus on it, but can you also become more coherent when you are not paying constant attention to it?

What and why will I be testing?

This brings me to the conclusion of today’s writing. How did I end up wanting to do a test on heart coherence?

In my mind I remember hearing somewhere that practising heart coherence twice a day for five minutes does something. This is quite vague, so I made an effort to get back to the source of this.

I have listened to a fair share of episodes of The Human Upgrade podcast and in one of them Dave Asprey2 (the host) sits with Rollin McCraty (PhD, director of research at the HeartMath Institute that sells the biofeedback devices) and they talk about coherence. They talk about the benefits of coherence and Rollin McCraty then mentions that he practises twice a day for five minutes and says that (for him) it is more than enough.

The “twice a day for five minutes” stayed stuck in my head and when I got the emWave pro, I decided to start testing this for myself. Will my resting coherence and HRV improve?

The exact protocol I will use is what I will write about next week. See you then!

References:

A lot of theory about coherence is provided by the HeartMath Institute. If you go to their website https://heartmathelearning.org/, there are quite a few free courses and also some paid ones. There is a module specifically on coherence.

This is not a HeartMath commercial; I just use their biofeedback device. It is worth mentioning that HRV biofeedback has also been researched independently. You can find the research here: Lehrer PM and Gevirtz R (2014), Frontiers in Psychology, Heart rate variability biofeedback: how and why does it work?

If you are interested in the specific podcast episode where I got my idea, you can find it here: The Human Upgrade.

Last week I talked about “the confounders”. This week I will talk about the tools.

It is worth noting that this equipment will provide me with numbers that might not necessarily be 100% accurate. This is not that big an issue, because I am looking for trends, not ad hoc information. Consistency will be key, so I will be using the same device(s) for the same measurements.

I will describe all items in roughly the following order: what it is and what it measures, what I will use it for and finally how much I trust it.

The list below is up-to-date for September 2026. If anything changes, during an experiment or in between experiments, I will mention it and afterwards also adapt this list so it will remain a reference document.

If you just want to know what device I use to measure which metric, scroll to the overview at the bottom.

AI:

My partner in crime, Claude by Anthropic. If you have not heard of Claude it is Artificial Intelligence, just like ChatGPT. It does not measure anything, but it can help me with just about everything else. I do not trust it blindly and I try to be as clear and specific as possible.

Claude’s own summary of the problem, which I agree with: language models produce fluent, confident text whether or not it is correct, so anything factual gets checked.

I use Claude for everything I would otherwise have to ask other people for. It helps me with brainstorming, checking my reasoning and pointing out things I had not considered. It helps me with technical aspects, like device specifications, and it proof-reads my texts.

While it would massively simplify things and save me a bunch of time, Claude does not write my texts …

Log app:

Last week I mentioned I would be logging a lot of things. One of the first things I asked Claude was to help me with an easy app for logging the things that matter. These include sleep data, how I subjectively feel, TM sessions, training and alcohol intake, among others. I wanted it on my phone, so I can use it everywhere and it registers immediately. Writing it down and digitising it later is not a habit that would work for me. The downside is that I have to use my phone almost immediately after waking up.

I have been using this app since mid-August, so I currently have a month of baseline data. The data is kept online, not locally. So I will not lose anything if something happens to my phone.

This app is the only tool I use that I have complete control over. I decide what goes in there and I adapt it if I feel it is not good enough. I will however not change the structure of the log during an experiment. I do not wish to fool myself or others.

While writing this I discovered I can adapt past inputs. I do not want to risk changing my inputs because I feel like I was perhaps wrong, so I will improve the app to make this impossible. As soon as I have fixed this, I will mention it!

Garmin Fenix 5X:

One of my oldest devices. I have had the watch since mid-2018, so it is perhaps not my most modern device, but it still does the job! It is bulky, sturdy, has already been through a lot, and the battery life is still very decent.1

The main thing it measures is heart rate. Besides that it also measures movement, steps, ambient temperature, barometric pressure and location-related data. From these it then derives information like training status and load, VO2 max, recovery, stress score, sleep stages and calorie estimates.

I mostly use it to track my sport sessions, but it is also a back-up for sleep and my step count. I have a chest strap I can use in combination with the watch to get more accurate readings. This is mainly useful for running. The strap is also my best bet if I want to get heart rate readings.

Since the watch’s optical sensor only measures on my wrist (I only wear the strap for running or biking), it does not provide me with the most accurate readings. The wrist moves a lot and is not ideal for optical sensing. It is still very useful for trends though and as a back-up for my ring.

For any sports experiments the watch will be my primary device.

Circular Ring 2:

The most popular and well-known smart ring is probably the Oura ring. Circular Ring 2 is a similar concept, except that there is no subscription needed after you buy the ring. After some research and since I did not want another subscription, I decided to back the Kickstarter project for the ring.

I have had a problem with my ring and then many problems with Circular’s customer support (I will not digress; it would not be healthy), but it has been up and running now since mid-August.

For such a tiny object, it is packed with sensors (PPG, thermistor and accelerometer) and provides a lot of readings. Sleep, Heart Rate Variability (HRV), Heart Rate (HR) and Resting Heart Rate (RHR), Breathing Rate (BR), temperature, SpO2, steps, to name a few. Since the last update it even measures Blood Pressure (BP). Since this is an estimation, it requires calibration with a BP reader.

The main reason I got the ring was to track my sleep. It never felt like the Garmin watch was providing me correct readings, so I wanted a second opinion. The Circular Ring will be my main “track everything” tool. I wear it non-stop with only a few exceptions, mostly related to manual labour, where it could get damaged.

For certain measurements, like (R)HR, HRV and sleep, the ring is better than the watch. The finger is a better location for optical sensors. For others, like movement or GPS, it is similar or worse. I also do not have absolute faith in the data it provides, but I will wear it more than my smart watch. These reasons are why I have decided to use it as my main device. Let’s hope it does not prove a risky bet, given the track record.

HeartMath emWave pro:

An interesting biofeedback device that focuses mainly on HRV. The emWave pro plugs into a computer USB port and has a wired optical sensor clip you attach to your ear lobe. This is a good location for optical readings, as long as it is not too cold. Since it is wired and you cannot move too much, the output is more stable. It gives a live reading of your HR and HRV and scores your coherence.

How exactly? By measuring the intervals between heartbeats, down to the millisecond. These intervals are never identical; the variation is called Heart Rate Variability. It can be irregular or smooth like a sine wave. The smoother it is, the higher your coherence score will be.

I use it to practise heart coherence breathing or to measure how coherent I am during certain activities, for example Transcendental Meditation.

The emWave pro uses a proprietary algorithm and has not been independently validated, but it has already been used in clinical trials. I trust the data, but I also know there are a lot of factors that can have an influence.

A few remarks:

• There are different challenge levels. The higher the level, the more difficult to score a high coherence. I will clearly define what I use before starting an experiment.

• Breathing directly influences your HR and can be used to manipulate readings. A BR of five to six breaths per minute (called coherent breathing) produces a high coherence score. This also means you can use your breath as a tool to train your coherence.

Omron M2:

A simple Blood Pressure reader. It is a clinically validated device, meaning it has been tested independently against standards set by the European Society of Hypertension. It gives me readings of my systolic and diastolic blood pressure and my pulse.

It is my primary device for measuring my BP and for this I do trust it quite a bit. Although it is clinically validated, the readings I get will be very dependent on when I take them.

I also use it to calibrate my Circular Ring once per month (required by the app), so that it can serve as my secondary BP reader, when I do not have the Omron.

Nokia Body+:

A simple smart scale that measures weight, fat percentage, total body water, muscle mass and bone mass.

I use it as my primary device to track my weight and for this I trust the scale, since it measures it directly. All the rest is estimated and nice to know, but I do not put too much weight on these numbers.

Medisana PM100 Connect:

A certified medical pulse oximeter. It meets certain regulatory requirements, but it has not been independently tested. You attach it to a finger and then get your oxygen saturation, heart rate and perfusion index (PI). It is meant for spot checking and not continuous monitoring. Since it takes time for the blood to travel to the extremities, there is a twenty- to thirty-second lag on the data you get.

I bought it while I was following my breathwork course. It was recommended (not this specific one, but just a pulse oximeter) to track some metrics while practising. It can show how long you stay saturated even while holding your breath and how your heart rate is influenced.

I trust the data, but with a caveat. The PM100 is attached to the fingertip, so if the blood flow is not good, vasoconstriction caused by breath holds for example, the reading might be off. The PI can be of help here. If it is low, trust the readings less.

CAROL bike:

The CAROL bike is basically a home trainer on steroids. It uses AI to adapt the training protocols to the user. The selling point is the Reduced Exertion High-Intensity Interval Training (REHIT) protocol. Some easy biking, two flat-out twenty-second sprints all in a minimum of five minutes. According to the manufacturer this is similar to a 45-minute run and could improve your VO2 max by twelve percent in eight weeks.

It measures your power output directly and your HR with a provided chest strap. It can also provide a VO2 max estimate, by either a ramp test or a submaximal test. The former mirrors lab protocols and is more trustworthy than the latter. Good for follow-up, not as an absolute value.

I bought the bike since the claim in the first paragraph intrigued me. As mentioned in last week’s post, I use it for my cardio training. While I think it certainly has its benefits and it saves me a lot of time, I have yet to properly test the claims. This is definitely on my radar.

Superhlth:

Superhlth is one of those holistic health-data tracking apps. It combines all your input (DNA, blood results, microbiome, wearables, etc.) and provides an overview of how healthy you are and gives advice based on AI. The company around the app also sells DNA, blood and microbiome tests.

Full use of the app requires a subscription; I just use the free version. I want to know how solid it is, before I get yet another subscription. Superhlth does not measure anything, but it collects data and then produces output like the Superhlth score, based on sleep, energy, nutrition and activity. It also gives an estimate of your biological age and shows you a “digital twin”. Biological age can be nice and flattering (or the opposite), but there is no standard way to calculate it.

I use it on a daily basis to log my food and nutrient intake. It uses AI protocols to analyse meals and give an overview of the nutrients you are getting. I doubt it is always correct, but it allows me to be lazy or, uhm let’s say, efficient.

I have also ordered their DNA test and track my blood work with the app. I do not regard the app’s interpretation as the absolute truth, but I find it very interesting and informative.

Again, the trend is what matters. The measurements and tests the app uses are sound, but they are interpreted by a proprietary AI model, which I do not yet trust fully. It is only my primary tool for food intake, not for anything else.

Overview:

A list of the metrics and what device I primarily use to measure them. This will be fixed during experiments and if it changes from one experiment to another, it will be documented. The current list is up-to-date as of September 2026.

• Coherence: emWave Pro

• HRV: Circular Ring 2 (rest and overnight), emWave Pro (during sessions)

• HR: Circular Ring 2 (rest and overnight), Garmin Fenix 5X (during training)

• RHR: Circular Ring 2

• BR: Circular Ring 2

• Sleep: Circular Ring 2, Garmin Fenix 5X (back-up)

• BP: Omron M2, Circular Ring 2 (travel)

• SpO2: Circular Ring 2 (rest and overnight), Medisana PM100 (spot checks)

• Weight: Nokia Body+

• Training load and sports metrics: Garmin Fenix 5X

• Power output and VO2 max: CAROL bike

• Food and nutrient intake: Superhlth

• Everything self-reported: log app

The habits described here will remain the baseline. I will log how well I stick to them and if any changes occur, I will document them.

“A confounder is a third factor that influences both the thing you're testing and the thing you're measuring, so it can produce an apparent effect that isn't really there — or hide a real one.” - Claude, in conversation while preparing this post1

With regards to sleep:

Sleep is one of those “non-negotiables” and one of the reasons I started this whole project.

I wake up after a good night’s rest (usually with an alarm) and I do not feel refreshed. I feel tired and want to go back to sleep. After I get out of bed this lasts for ten to fifteen minutes and then I am mostly fine and can go about my day.

Consistency is what I am aiming for right now. Every morning my alarm goes off at 0600. Sometimes I get up immediately. Sometimes I snooze, but I try to limit this bad habit. I never considered myself a morning person, but I do enjoy being able to get stuff done early!

In the evening I get in bed and go to sleep between 2200 and 2300. I usually read something before bed, wear blue-light-blocking glasses after 2100 and try to limit my screen time. Not always possible, since a daily video call with my girlfriend often takes place around this time as well. When I actually go to sleep, I put on a sleep mask (to block any remaining light), turn my air filter to sleep mode and open the window to let some fresh air in. Oh, and I sleep naked; this allows my whole body to breathe a bit at night ;)

This gets me between seven and eight hours of sleep per night, which is currently a good number for me to aim for. My energy levels seem fine and so does my sleep debt2. How on earth do I still wake up feeling tired?

Of course there are days when I cannot stick to these hard timings. Life happens, I am not a robot, and do not wish to be one. This happens perhaps a couple of times per month, but I rarely sleep less than seven hours. Exceptions will be documented, so the impact on a running experiment will be visible.

All of this matters, because sleep quality and duration strongly affect most physiological measures. My sleep might be good and stable now, but that could change in the future. Room temperature, for example, is one of the things I cannot control precisely and it will change with the seasons. If anything changes, it will be logged and published with the results.

With regards to sports:

Once upon a time I was very active and easily did over ten hours of sports per week. Right now I tend to stick to a minimalistic routine. Enough to keep me in shape, without taking up too much time.

I do three gym sessions a week for some strength training. These are usually somewhere between 1500 and 1700. Since I do not mind some repetitiveness, I mostly do the same exercises and I try to limit the whole to thirty minutes. After the training, the infrared sauna awaits me for a fifteen-minute session. Here I often play around with my breath; what else should I do?

For cardio I use my CAROL bike when I am at home, otherwise I will just go for a run. Three rides per week on the days I do not go to the gym, almost always in the morning before breakfast. A standard REHIIT training session takes about eight minutes and forty seconds. This is supposed to have the same effect as a 45-minute zone 2 run. I got the bike to test the claim, but so far I have not set up a protocol to do this. I enjoy the bike and I am under the impression my cardio remains decent.

When at home the consistency of the training sessions is pretty good so the training load should not vary much. It does, however, mean that most of my measurements will happen while my body is still recovering.

During the weeks I travel, about once a month, I try to keep a similar schedule, but I manage it less consistently. The sessions will be logged no matter what, so the impact can be analysed.

All of the above can have an impact on measurements. Breathwork affects the nervous system, my body is rarely fully unloaded and with the REHIIT I practise maximal effort three times a week. As mentioned, everything will be logged so it can be checked against the results.

With regards to meditation:

I usually practise Transcendental Meditation (TM) in the morning. I hope my teacher will not read this publication, because you are supposed to have two TM sessions per day. An afternoon session is just not that easy to fit in. I try to have at least one session daily, but this can be difficult when not at home.

The TM lasts for about twenty-five minutes, during which I focus on my mantra, while trying not to focus too much on my mantra.

The TM sessions are likely to affect the nervous system. The impact might not be as big as with two sessions per day, but it is nevertheless something to take into account. The number of daily sessions will be logged and published.

With regards to food and drink:

I stick to time restricted eating (TRE) as much as possible. This basically means I only eat during a specific timeframe and it is easier than it seems. My “eating window” is currently between 0800 and 2000. The other twelve hours of the day I am in a fasted state. I sleep about eight of these twelve hours, so only four waking hours are spent not eating. Around 0800 in the morning I break my fast.

Outside of my eating window I drink water, tea or coffee (not in the afternoon), with one exception. My morning coffee is always mixed with 5g of creatine and two out of three times I add butter and C8 MCT oil. Whether or not this really breaks the fast I am not sure, but it definitely could.

I try to pay attention to what I put in my body. The quality of the ingredients matters. In general I try to buy bio or organic and not too many processed things. This is negotiable though. It can be rather expensive and you can only control it when you make your own food.

As far as alcohol is concerned, I do not drink very often. When I do it is either at social occasions or the occasional glass of wine or beer at home.

The eating pattern is stable when at home and I try to adhere to it as much as possible when not. I keep a log with times and what I eat3. Days where I have alcohol or eat late will be marked so any effects will be visible.

With regards to supplementation:

The supplements I take are all linked to identified deficiencies and they will not change before getting my next blood work done.

A list of what I currently take:

• Creatine: Body&Fit (Creapure), taken with my morning coffee

• Omega-3 fish oil: Eqology Pure Arctic Oil

• Vitamin D and K: Eqology K2+D3

• Vitamin/mineral supplement: Eqology Nordic Energy Booster

• Zinc: DeBa Pharma Zink-forte

• Copper: Solgar Chelated Copper

On top of this I regularly take some chlorella/spirulina tablets, but these could be considered a food rather than a supplement.

Full disclosure: I have been using Eqology products since June 2026 and I have been a business partner since September 2026. I am not selling any products here, nor will I put up any links, but you should know.

Since these are stable, they are not really confounders. They are worth mentioning because they might be adapted based on blood tests. When this happens, it will be documented.

With regards to morning rituals:

After feeling horrible for a few minutes (perhaps a slight exaggeration), I finally get up and start my morning rituals.

I get out of bed and have a few sips of water. I go to the bathroom for a morning pee and afterwards get on the scale to check my weight. After the weigh-in I have a timeframe for logging experiments and once this is done, I start the TM I mentioned earlier.

About an hour after getting up it is time for my morning coffee and breakfast, so no caffeine before measurements. While I have my coffee and before I have my breakfast, I do my Duolingo (I have a streak to keep up, mind you), some brain training games (Lumosity) and read. This is also where I do a REHIIT session on the days I do not go to the gym.

Most of my mornings (over seventy percent) look like this. The remaining thirty percent is where the variation comes from and the reason for logging. I will always describe the experiment protocol beforehand and fit it neatly into this ritual.

To summarise:

All of the above makes my life seem very structured, but believe me, it is not. One or a few days a week I work; some days I am renovating my house. Meanwhile I spend quite some time in Sweden with my girlfriend and on top of that I am working on transitioning from the military to the sports/health sector. And there is always a chance I might fall ill. My life is very flexible right now.

This matters because it means a lot of variation that can have an impact on the experiments I will be running. No matter what, the variation will be logged and the confounders can be checked against the results.

Thanks for sticking with me, see you next week!

Yannick

I can sleep anywhere, anytime and for at least 10-12 hours straight. I have been like this ever since I was a teenager.

Sounds great, right? Except that I always wake up feeling like I could sleep some more. My sleep quality is fine; my waking-up quality, less so. In a way, you could see Homo Optimus as my quest to wake up refreshed.

This quest has really taken off in the last couple of years. In 2025 I became a breathwork instructor, started tracking my metrics, experimented with supplementation and learned transcendental meditation, among other things.

I still wake up feeling tired.

But along the way, I feel other improvements. I am learning more about my body and how to listen to it. I now know which nutrients I get enough of and which I am short on. I am learning how to create new habits. In short: I am becoming an optimal version of myself.

The question remains though: what works and what doesn’t? There is no point in having a habit or taking a supplement if you cannot tell the results. That is why I check my blood values, why I track my metrics and why I started Homo Optimus. I want to know if what I do works, but most importantly, I want to know if it does not.

As a breathwork instructor, for example, I want to know whether I become more coherent if I start practising (heart) coherence regularly. Feeling the effects is one thing; backing them up with data is another. Therefore I will run monthly experiments, with the protocol published before I start.

In the end, the goal is to feel good. Having data to back it up shows what works and what doesn’t.

So tag along, but don’t get lost in measurements!

Yannick