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Heart on Willem's Blog

Health and fitness data

Is more better?

Jan. 16, 2024
Exploring the balance between health data and intuition, this blog post delves into how personal well-being and fitness goals shape our relationship with technology and self-awareness.

Since the start of this new year I am working out harder than the previous months. I have set some goals for myself and have taken on a training scheme incorporating running, cycling and swimming. As I sift through the growing mountain of workout data, I find myself questioning: does having more data truly translate to better fitness outcomes?

Impact of training

Analysing WHOOP's trend data

May 31, 2023
Join me on an intriguing journey as I explore the transformative impact of effective training and data analysis on my performance in the Fietselfstedentocht 2023.

This Monday I completed 235KM on my fixed gear bike during the Fietselfstedentocht 2023. It was a nice ride with fair weather and favourable wind conditions. Yet, I took the challenge seriously and prepared myself with some proper training. In this post I'll have a look at the trend data from my WHOOP in preparation for the Elfstedentocht.

Tips for Long-Distance Cycling

Riding 204KM on a fixed gear bike

Apr. 20, 2023
Embark on your own long-distance cycling adventure by learning from my post-COVID Fietselfstedentocht experience, packed with invaluable tips and tricks.

In preparation for this year’s Fietselfstedentocht (236KM), I took my bike and set out for an adventurous ride through half of the Netherlands. It was my first long distance ride after being infected with COVID. If you're considering a long-distance ride yourself, be sure to read along to discover invaluable tips and tricks from my experience.

Wearing WHOOP 4.0

Why you should wear a biometric sensor

Jan. 14, 2022
Use WHOOP to see the impact your choices have on your body, think of it as a special kind of mirror - it's so powerful, that I don't take mine off!

How often do you look in the mirror? Probably more than a few times a week! I have been thinking about this ever since I received my newest WHOOP 4.0 biometric sensor. It's great. But, why do I wear it? What value does it provide? Why should you wear it?

Riding with Omata One

Analogue cycling computer with GPS

Sep. 29, 2020
If you're looking for an alternative for common cycling computers, the Omata One is something truely special: it indicates your speed, distance, ascent and time ridden using mechanical hands!

For the past week I have been riding my bicycle with Omata One, a special bike computer. Its mechanical hands indicate speed, distance, ascent and time ridden measured using precise GPS data. It is fun, read along to know why.

Measuring cholesterol levels in blood

Know your LDL, HDL and Triglyceride numbers

Jan. 28, 2020
This week I had my blood examined to measure my cholesterol levels, taking a lipid profile. Know your LDL, HDL and Triglycerides numbers with a simple test.

This week I went to my doctor to have my blood examined, to determine my cholesterol levels. Over the past years I have been paying more and more attention to my health. After improving my lifestyle considerably, I wondered what my numbers were.

Improve your sleep by blocking light

On the benefits of wearing a sleep mask in bed

Jan. 24, 2020
I have been wearing a sleep mask in bed, blocking all light. It has been amazing for my sleep's quality. Read along for my findings!

Over the past few weeks I have been experimenting with wearing a sleep mask in bed, blocking all light. Our bodies produce the sleep hormone, melatonin, in darkness. Living in an environment awash in artificial light, is therefore exactly the sort of thing that disrupts one's circadian rhythm. Can a simple mask help?

Whoop strap review: 24/7 wearable sensor

Beyond fitness tracking and smartwatches

Dec. 31, 2019

The past months I have been wearing the WHOOP Strap 3.0, a wearable sensor that collects health and fitness data. It's different compared to most other fitness bands as it was designed with professional athletes in mind. It is focussed on daily strain, recovery and sleep. Read along to find out how this works.

Riding with a power meter on your bike

Installing and using the 4iiii Precision Powermeter

Aug. 28, 2019
In this post I describe my experience with installing the 4iiii Precision Powermeter on my road bike.

After I created a minimal road bike, I decided to install a power meter to find out what's it like to measure the power output of my legs. What can you learn from a power meter? Is it difficult to install? Is it worth it? Read along to find out.

Limitations of sleep tracking using a wearable

Comparison with a chest strap HR-monitor

July 16, 2019
Limitations of heart rate analyses during sleep, why you should reconsider tracking your sleep.

Sleep monitoring is a popular feature of many smartwatches and wearables. Devices like Fitbit, Withings, Apple Watch and Biostrap analyse biometrics during your sleep. These wearables are worn on the wrist and use optical sensors to capture your heart rate. I wondered how the optical sensors would compare to a high resolution chest strap HR-monitor.

Optical vs chest strap heart rate monitors

Measuring beats per minute using different sensors

July 15, 2019
Understanding the differences in common HR monitors used in wearables, smartwatches and fitness trackers

With modern wearables, smartwatches and fitness bands, it has become easy and common to measure your heart rate. There are however fundamental differences in sensor types. Some sensors capture the electrical signal from your heart while others use light to analyse the blood flowing through your vessels. If you're interested in measuring heart rate, it's good to understand these differences.

Solo around the Markermeer (211KM)

Tips to prepare, to endure and to enjoy long distance cycling

May 29, 2019
This week I took my bike for a long distance (211)KM ride around the Dutch Markermeer, solo! Read along for practical tips for long distance cycling.

This week I took my bike for a long distance (211KM) ride around the Dutch Markermeer, solo! Unlike participating in an organised event with service, support and company along the way, going solo requires a different preparation, mindset and planning. Read along for some practical tips for long distance cycling.

The best bike computer app: Cyclemeter

Get advanced ride data with a flexible setup

Apr. 30, 2019
Collect advanced bike ride data using your smartphone connected to external Bluetooth sensors and a steer mounted display.

This month I have intensified my training to become fit for this year's Fietselfstedentocht, a 235KM bicycle ride through Friesland. Over the years I have tested different kinds of bike computer setups: from dedicated (and expensive) Garmin Edge bike computers to no data at all. Eventually I came up with a flexible setup to gather advanced ride data using my smartphone, let me explain how this works.

Born with MCADD

Medium chain acyl-CoA dehydrogenase deficiency

Jan. 29, 2019
Our son was diagnosed with MCADD days after he was born. We experienced a metabolic crisis but were lucky to be just in time!

Just days after our son was born, we ran into trouble when our little man didn't want to eat anymore. Repeated attempts to feed him failed as he appeared to be too tired to drink from his mother. When we measured his body temperature we were shocked, only 33º Celsius! What followed was nothing less than an incredible emotional rollercoaster!

My first weeks as dad

On the challenges and rewards of being a father

Jan. 24, 2019
Last Christmas my wife gave birth of our son. It's a life changing experience to become a parent. Read along for my (biometric) findings and some practical tips.

Last Christmas my wife gave birth to our son, a little boy that would change everything! It's an incredible experience to become a parent, especially if it is your first kid. It introduces a whole new way of living, having to deal with regular feeding, caring and sleepless nights. Read along for my (biometric) findings and some practical tips!

Do amazing things with a focused mind

Taking an ice bath and swimming in the Amstel river

Dec. 6, 2018
Read about my experience during the workshop I got as a birth day present involving the Wim Hof Method.

Just when the temperature was a low 2° Celsius, I jumped in the Amstel river! While it was nearly freezing outside I went for a swim, just moments after I've taken an ice bath! This post is about the incredible birthday present I got, a workshop involving the Wim Hof Method.

Swimming and cycling with Apple Watch

Different activities in the workout app in watchOS

Sep. 27, 2018
This month I tested the newest watchOS while swimming and cycling.

This month Apple launched a new Apple Watch series and released an update to watchOS. The focus of the smartwatch is more and more gearing towards health and fitness. This made me curious, how well does Apple Watch work for different activities?

Listen to your body

Why I stopped using health and fitness sensors

May 17, 2018
Using health data gathered by sensors and wearables I learned to listen to my body. Now I have stopped using bluetooth sensors all together.

A good customer of mine was once a physiotherapist, he told me about people asking him to "feel their muscles" to tell them how they where doing. "Crazy!" he told me: "I can never feel better than the people themselves, if they only would listen to their body". This caused me to question the health and fitness sensors I use.

Outside the comfort zone: amateur acting

Wearing an heart rate monitor during my debut performance

Apr. 18, 2018
This month I strapped myself with sensors during a little experiment outside my comfort zone: I debuted as amateur actor!

This month I made my debut as amateur actor. I am no Hollywood star, nor do I envy to become one. But I do like crazy experiments and operating outside of my comfort zone often leads to new and refreshing insights. I took part in an amateur drama play and - in the name of science and fun - strapped myself with sensors to measure what happened to my body.

Commuting by bike

One week (240KM) on the VanMoof Electrified S

Dec. 2, 2017
One week on the VanMoof Electrified S E-bike testing it for commuting and comparing it to a normal bike.

For a few years now, I commute to work using a bicycle. I have lost more than 15KG since I stopped using my scooter. This week I tested a VanMoof Electrified S, an electric bike with an industrial, minimal design. Is it any good? How does it compare to a normal bike? Will an electric bike make you lazy? Read along to find out!

Collecting health data with Biostrap

Wearing a clinical-grade photoplethysmography (PPG) sensor for a month

Nov. 15, 2017
Wearing a clinical-grade PPG sensor for a month to collect advanced biometrics from my wrist.

Most wearables (smartwatches, fitness trackers, etc.) use very basic sensors to capture heart rate. Their signal is binary: just counting beats. Biostrap is different, instead of just checking pulses, it captures a high-fidelity PPG waveform. These waveforms are the same kind that doctors use, making me wonder what I could learn from them!

Fietselfstedentocht 2017

Cycling the 235KM bicycle tour through Friesland

June 30, 2017
Cycling the 235KM long Fietselfstedentocht through Friesland

This month I cycled the Fietselfstedentocht, a 235KM tour through Friesland. This tour brings you through various Frisian cities throughout one of the most Northern provinces of the Netherlands. The tour was first organised in 1912 and has grown to become legendary due to its history, challenge and popularity; well worthy of a blog post!

All blog posts
Bike in the local bike shop
Bike in the local bike shop "werkplaats" (Dutch for workshop)
Maasduinen National Park in Limburg
Maasduinen National Park in Limburg
The crank arm has it's model and length written on it, on my bike that's: FC-5800, 172.5MM
The crank arm has it's model and length written on it, on my bike that's: FC-5800, 172.5MM
My completed Fietselfstedentocht 2022 stamp card - note how the edges have been through bad weather...
My completed Fietselfstedentocht 2022 stamp card - note how the edges have been through bad weather...
Riding my bike as workout (photo by Niels)
Riding my bike as workout (photo by Niels)
Maybe it's the font, maybe it's her haircut, but somehow I get a 80s vibe from the Mindfold's packaging :-)
Maybe it's the font, maybe it's her haircut, but somehow I get a 80s vibe from the Mindfold's packaging :-)
Beyond individual metrics: WHOOP provides a complete insight, including recovery, strain and sleep
Beyond individual metrics: WHOOP provides a complete insight, including recovery, strain and sleep
The Omata One uses four mechanical hands to indicate speed (orange), distance (outer ring), ascent (left) and elapsed time (right)
The Omata One uses four mechanical hands to indicate speed (orange), distance (outer ring), ascent (left) and elapsed time (right)
You're amazed by the things you'll encounter - like the beauty of the Dutch National Park Hoge Veluwe...
You're amazed by the things you'll encounter - like the beauty of the Dutch National Park Hoge Veluwe...
My heart rate during the 10 hour ride from Amsterdam to Hegelsom: note how I kept my heart rate relatively low during the first few hours!
My heart rate during the 10 hour ride from Amsterdam to Hegelsom: note how I kept my heart rate relatively low during the first few hours!
Conductive pads in the chest strap work in a similar way as the heart rate monitor in hospitals
Conductive pads in the chest strap work in a similar way as the heart rate monitor in hospitals
Different strap styles and lengths
Different strap styles and lengths
The ProKnit strap is made of fabric, it is comfortable, stretchy yet sturdy and dries quickly
The ProKnit strap is made of fabric, it is comfortable, stretchy yet sturdy and dries quickly
Training opportunistically: working out on a foldable bike during some days from home - you're certainly attracting some attention in full lycra on a Brompton!
Training opportunistically: working out on a foldable bike during some days from home - you're certainly attracting some attention in full lycra on a Brompton!
The WHOOP sensor is small - smaller than many regular watches
The WHOOP sensor is small - smaller than many regular watches
WHOOP 4.0 is smaller than its predecessor - packs more sensor technology - allows for easy charging while wearing it
WHOOP 4.0 is smaller than its predecessor - packs more sensor technology - allows for easy charging while wearing it
WHOOP Strap 3.0 can broadcast your heart rate to any Bluetooth device
WHOOP Strap 3.0 can broadcast your heart rate to any Bluetooth device
The Mindfold sleep mask: total darkness with your eyes open
The Mindfold sleep mask: total darkness with your eyes open

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