10 years of HRV4Training

Thank you for your support

Indie. Forever.

10 years ago I started building HRV4Training, coding the app and blogging.

We somehow managed to do things our way and still put food on the table for the past decade.

Over this time period, more than 1 million people ended up on the blog. Many have been using our tools and have been in contact with us, leading to what will be lifelong relationships and friendships.

I am truly grateful for the many opportunities this work has led to, especially in terms of human relationships.

Here is a bit of our story.

Thank you for your support.

How did it start?

I had no master plan to work on heart rate variability (HRV), or even with anything related to it, or in sports science.

Many years ago, while studying computer science engineering, I found myself with little interest in the various topics that were part of my field (computer networks, computer graphics, programming in its various forms, cryptography, etc.).

Nothing really clicked until during the last year of my masters, I took a course on what was called “embedded systems”. Basically, sensors placed on the body or in the environment, which would sense stuff, to then be processed. This was 15 years ago.

Through this course, I had the opportunity to move from Italy to The Netherlands, and ended up at IMEC, the largest R&D institute on nanotechnologies in Europe. In particular, IMEC had a branch that worked on the development of what we called “body area networks”. There, I started building hardware, firmware, and software for sensors that could measure brain activity, heart activity, movement, muscle contractions, and more. These were the early prototypes of today’s wearables.

In 2009 I hacked the SD card slot of the first Android phone to communicate with an external sensor that imec built, and transmit an ECG.

For me, as a computer scientist, it was extremely fascinating to be able to use my skills to measure, analyze or estimate the body’s response to different aspects of daily life. As a child, I had always been a builder. Software was a great match as I could build with limited or no costs.

After a few years of working on the development of these sensors, I went back to my computer science roots and did a Ph.D. in applied machine learning, working on the estimation of energy expenditure and cardiorespiratory fitness (VO2max) from data collected with these sensors. During these years, thanks to my colleagues and the experiments they were doing in the context of work-related stress, I learned about HRV.

Timing

As I was learning about embedded systems, sensors, hardware, firmware, and building prototypes, the first smartphones came out.

I was lucky to be doing what I was doing at the right time. Thanks to developments in technology, it was now possible to code apps and build tools that for the first time, potentially many more people could use.

I always loved building tools, hence I started coding on Android and later on iOS (when iPhone started supporting the Bluetooth low energy protocol, which allowed for communication with third-party sensors like Polar straps), building 28 apps before I finally built HRV4Training.

It took us 2 years to pass 1000 USD / month in sales. No rush.

A side project

I studied, I built tools, I self-experimented, I learned from the literature, and I learned from other people doing similar work. I then moved to the US to start a company, focused on the development of a new sensor to measure uterine activity during pregnancy, and potentially unveil relationships between changes in physiology and pregnancy complications.

For this entire time (~5 years or so) I kept HRV4Training as a side business. I was still learning, interacting with users, studying the science, improving the app, and I loved not to depend on it financially. It was a happy place I could always go to.

I was never on this planet to convince others of anything, or to sell anything. I am here to build, and to communicate to whoever is interested in what I am building, which meant that a side project was really a good fit for me. Pitching, raising money, growing, were never my concerns. Despite living in San Francisco and hearing that kind of music 24/7, never I thought it was the way I wanted to do it.

After a few years of cultural clash, I moved back to Europe and went back to University to study sports science, to deepen my knowledge of the topic I ended up working in, thanks to HRV4Training. I wanted to make these tools even better, and to help people using them along the way.

During these 15 years, I got 4 degrees, started 2 companies, and published about 50 papers in peer-reviewed journals, plus a few patents. HRV4Training has been there almost the whole time, as an idea, as a side project, as my main activity, and sometimes, as part of my identity.

It has been quite a journey and I am grateful to have met many of you along the way.

Visits on our blog over the past ten years came from all over the world. Despite the financial struggle of this business model, we are doing what we can to keep the tools low cost so that almost anyone with a phone can use them.

Choices

My choices have been quite unusual in our line of business.

As a tech entrepreneur in Silicon Valley almost 10 years ago, the regular path would have been to raise money from anyone that would give you any - with no ethical concerns - then invest in questionable marketing strategies, and after a while, sell your company, so you can make some money, and maybe switch roles and become an "investor". That’s a success story according to some.

That’s just not me.

It took me many years to learn to balance my life better. Exercise helped a lot.

Almost 20 years ago I met a Alessandra. She has been an essential part of my personal growth and has shaped how I see the world today. Through her life and work in education, using art practices as tools for social change, she has constantly challenged the bubbles I lived in (technology, Silicon Valley, capitalism as the only system). While this is not a political essay, I owe her who I am today and wish more people with my background would be exposed to views others than the ones pushed by their own bubble.

There are other ways to do things. There’s community, there’s cooperation. The rethoric of crushing the competition and taking over the world is unfortunately still strong. Conversations with good friends that are at least partially brainwashed by that type of thinking made me think more about external pressure and how I want to live.

For me, once I can eat, the choice is very easy: time comes before money. Mental and physical health come before money. I value quality over quantity, ethics above all. My path is not "the right path", but it is the right path for me. It’s a path of cooperation and human relationships.

Here are some of the choices I made over the past ten years, in line with my values:

• I turned down absurd salaries in the Bay Area (250K USD / year) to pay myself not even 20% of that and stay in charge of my day and time.

• I moved back to Europe where we pay 40-50% of our salary in taxes so that the vast majority of us can get a decent chance at life (as I did, see below).

• I turned down a green card for similar reasons, U.S. rhetoric is as far as it gets from my own (please don't take this personally).

• I turned down acquisitions: doing what I love on my own terms is priceless.

Obviously, I was fortunate to be born in Italy, where the welfare state gave me almost all that I needed to get here: almost zero costs for medical care and education until I left the country in my 20s (good grades were enough to get full support from the state as my family had little and split up when I was a kid).

While aware of my privilege, I did make lots of uncommon choices for people that were in a similar position.

These choices don't have to be yours as well, we travel different roads and might have different values, but make sure to think your choices through, you do have control over many of them.

Don’t play other people’s games, the clock is ticking.

What made a difference?

Looking back, I think the following aspects have been key to be able to build what we built:

• Finding the right niche. HRV wasn’t what I had planned, or the first thing I tried, but it ended up being just the right thing: there is a strong scientific background on the topic (i.e. we are not making things up, which would make me very uncomfortable) but we don’t really understand it fully either (hence I am constantly challenged and haven’t gotten bored just yet). Business wise, focusing on a small niche, relying on the unique technology I was able to build (the first camera-based HRV measurement system), was essential.

• Executing. Everyone is looking for that great idea, but ideas are often overrated, and getting good ideas is easy. Try this simple exercise: start thinking on a daily basis about what problems you could solve, take 30 minutes, challenge yourself. You’ll be blown away by how many good ideas you can get. Then the hard part really starts: execution. At the end of the day, much of it comes down to knowing what you are doing and not getting derailed all the time (by founders, investors, or users). If you are building something, you must be the expert. Keep learning and studying every aspect of it. If you can be a user of what you are building, even better. I have often built what I needed / wanted for me.

• Having very limited resources. This might seem counterintuitive, but having very limited or no resources made execution a lot easier and better over time. Too much money, time, employees, and users, and you end up building a lot of useless things and turning a useful product into a broken toy. I built continuous HRV tracking in 2014. I looked into sleep tracking and HRV with an Apple Watch in 2016. These ideas died on my desk because the science and the technology are flawed. If we had more resources, or “needed to grow” or to keep users and investors entertained, maybe we would have built something, the way some wearables are doing today. I am glad we didn’t. Lack of resources was (and still is) a blessing. Funnily enough, ten years and many technological developments later, the best way to track your resting physiology is still first thing in the morning.

• Developing thicker skin. I had none when it started and it was rough. Many people will love your apps and they’ll write you emails longer than this blog on a daily basis. They’ll be doing the most interesting tests, experiments and ask for your support. You’ll collaborate with brilliant people all over the planet. However, there’s one thing they will not do. They won’t review your app. The haters instead will love reviewing your app. Over the years I have collected a neverending list of insults. For many years I took it very personally - I was building it after all. I was often miserable. I overreacted. It took me a while to learn to deal with this, but you know the saying, what doesn't kill you…

• Finding your way of promoting your work. I have never paid for ads or people to promote our product. We just don’t have the resources nor we believe that’s the way to go. Instead, I write a lot. I talk about what I do. It could be ramblings like this blog or posts about the physiology or technology of HRV measurement. I try to show how others can benefit from my work, and this has become an essential part of it all. Eventually, this is what led to many collaborations with likeminded individuals and companies. I did podcasts with Jason at Elite HRV, I try to help Oura every way I can, I built algorithms for Strava, I had great conversations with people at Firstbeat and Biostrap, and the list goes on. Be open, write, cooperate.

How is it going?

When asked this question on a podcast, I typically say “good”. When asked by a friend, I am more hesitant.

I too fall in the trap of thinking that selling less than last year is a problem, or that “competition” is troubling us. If I get my head out of my ass and stop seeing everything through a capitalist lens, then it is indeed going good. I love what I do. I love interacting with the people using our tools. I love how I spend my time during the week.

10 years is a long time. Most startups don’t make it that far, and we are still here. We keep building, we keep interacting with brilliant people and growing both personally and professionally. I could not ask for anything more.

Doing it all with a very small team is hard. The only way we can survive is for me to do all the technical work (iPhone app, Android app, backend, frontend, data science, algorithm development and implementation, etc.). I have not been more than 24 hours far from my computer in a decade. Two months ago, after running 100 km through the night, I went back to my hotel room and replied to customers emails. Sometimes these things get to me as well.

How is it going?

Good.

We were really fortunate to have Daniel join our team when we decided to go all in about 5 years ago. This is HRV4Training.

What is next?

This is my least favorite question, so I figured I’d ask (and answer) it too.

I dislike the what’s next question for a number of reasons, starting from how I think it reflects our inability to live and appreciate the present and what we have been doing so far.

Sure thing we need to move forward and look forward to the future, but what I would like to do next is nothing more than what I do today. And that’s fine.

I want to keep building tools that allow anyone with a phone to measure and interpret their physiology reliably, so that they can better understand how different aspects of life impact their health and performance. That’s exactly what I have been doing for the past ten years.

Are we done with this? Do we all understand technology and HRV? Do we understand how different stressors impact our physiology? Do we understand how to adjust behavior based on our physiological responses? Do we know what to expect when we adjust behavior based on physiological responses?

That’s what I thought.

Thank you again for supporting our work over the past decade.

We’ll try to stick around a little longer!

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Ways to Show Your Support

No paywalls here. All my content is and will remain free.

If you already use the HRV4Training app, the best way to support my work is to sign up for HRV4Training Pro.

Thank you!

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Marco holds a PhD cum laude in applied machine learning, a M.Sc. cum laude in computer science engineering, and a M.Sc. cum laude in human movement sciences and high-performance coaching.

He has published more than 50 papers and patents at the intersection between physiology, health, technology, and human performance.

He is co-founder of HRV4Training, advisor at Oura, guest lecturer at VU Amsterdam, and editor for IEEE Pervasive Computing Magazine. He loves running.

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