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Lifestyle on Willem's Blog

Marathon

Running my first full marathon

Oct. 20, 2024
Read the story of how it feels to complete your first marathon.

Last Sunday I completed my first full marathon, covering a distance of 42KM in and around Amsterdam. An idea that started in a bar with some beers and concluded with a finish in the Olympic Stadium. What a journey, what an experience, well worthy of a blog post.

Developing a native iOS app

Making a cycling and running tracker

May 11, 2024
How hard can it be to build your own cycling and running workout tracker app using native code with some help from AI? Read along to find out!

As a little side-project, squeezed between my normal work, I have been working on something of personal interest: a native workout tracking app for iOS. I wanted to make my smartwatch obsolete, instead using my phone to track workouts. How hard could it be to gather detailed sensor data using native Swift APIs?

Half Marathon

On Training, Data and Feeling

Mar. 24, 2024
Discover my journey from noob to (half) marathon finisher and how I balanced data with fitness - read about my experiences!

Last Sunday, I participated in the Venloop, a half marathon event in Venlo. I completed the 21KM run in 2h05, a result I am satisfied with as this was my first ever 'official' event since I began running just three months ago. In this post, I'll share my experiences with training, balancing fitness data, and feeling fit.

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?

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?

The birth of a child

Impact on daddy and his biometrics

July 13, 2021
Witnessing the birth of a child changes a man, for science and curiosity I wore a biometric sensor capturing the impact of birth on yours truly.

Today I witnessed the birth of my daughter! You feel humble as a man, witnessing the labour and magic. Not sure if I can come up with something having more impact on a man than this. For the purposes of science and curiosity I wore a biometric sensor, and this is what it recorded.

Fixed Gear Gran Fondo

Cycling 176KM through rain and wind

Apr. 10, 2021
Taking a fixed gear road bike for a gran fondo! Let some of my fun be of inspiration to you!

Today I took my fixed gear bike for a ride, 176KM from Amsterdam to America (Limburg, The Netherlands). Rain and wind added to the challenge, creating an ultimate test for man and machine. Let some of my fun be of inspiration to you!

Commuter bike checkup

How is my commuter bike doing after 21.000KM?

Jan. 10, 2021
This week my trustworthy commuter bike started making strange squeaking noises when braking, time to have a look at the bike after 21.000KM!

This week my trustworthy commuter bike started making strange squeaking noises when braking. It has been just over three years since I started cycling on it. People frequently ask me how the bike is performing and how the Gates Carbon CDX belt drive is doing? Time to have a look at the bike after 21.000KM!

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.

Different ways to visualise health

Looking at games and fitness apps

May 25, 2020
To better understand how to visualise health I looked at different health/fitness apps and games.

This month I did some research into how health is visualised in fitness apps and games. For a new app involving personal health I am looking for an intuitive way to visualise how healthy one person is. There are many colourful approaches out there!

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.

Six months with MCADD

Thoughts and tips on the daily life as parents

June 24, 2019
It's six months since our son was born with MCADD, a good moment to reflect upon the experience of being a parent with some thoughts and tips.

Tomorrow it's six months since our son was born, a good moment to reflect upon the experience of being a parent of a kid with MCADD. This metabolic condition demands special attention on the feeding schedule and preparation for situations when things go different. It's good to share that this has quickly become normal for us, here are some thoughts and tips.

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.

One year on the ultimate commuter bike

6000KM in 12 months with Gates CDN/CDX and Shimano Alfine

Feb. 27, 2019
Answering questions from one of the most popular posts of last year, I am reviewing my commuter bike after one year of extensive use through winter and summer.

A year ago I tried to create the ultimate commuter bike, a modified Sensa Cintura with the Gates CDN/CDX carbon belt drive. I received lots of messages from cyclists and commuters from all over the world. From the Swiss alps, France, Italy, Germany, United States and even "down under", Australia! You all wanted to know: how does the upgraded bike hold up?

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?

Enjoy a festival without alcohol

Alcohol-free beer at Rock Werchter

July 10, 2018
This year I didn't drink alcohol during Rock Werchter, leading to interesting observations during the music festival.

Last weekend me and my brother went to Rock Werchter, a multi-day, music festival in Belgium. Over 140 thousand visitors enjoy world famous artists like Pearl Jam, Nick Cave, Artic Monkeys, Noel Gallagher, The Killers and the Queens of the Stone Age. This year I didn't drink alcohol during the festival, leading to some interesting observations...

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.

Creating the ultimate commuter bike

Riding at 35KM/h with Nexus Alfine 8 and Gates Carbon Drive

Feb. 24, 2018
Creating the ultimate commuter bike by upgrading the Sensa Cintura belt drive bike.

This winter I use a Sensa Cintura bike with a Gates Carbon belt drive as my daily commuter. It's a bike designed to be nice to ride thanks to its sporty lightweight frame. It's also meant to be low on maintenance thanks to the belt drive and Nexus Afline 8 integrated gear hub. After 1800KM in just eight weeks, it was time for some upgrades.

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!

Smartwatches vs Mechanical watches

Why I still wear mechanical and why smartwatches have potential

Apr. 30, 2017
Why I still wear a mechanical watch and why smartwatches have potential.

Technology has come a long way since the first computer. Smartwatches today are very much an achievement of miniaturisation of technology. I recently used an Apple Watch Series 2 to find out if technology has come far enough to replace my mechanical watch, today I share you my findings.

One year of cycling

GPS recording an entire year of bike rides using Garmin and Strava

Dec. 31, 2016
GPS recording an entire year of bike rides using Garmin and Strava.

One year ago I started recording all my bike rides, including commutes, short grocery trips and long Gran Fondos. I equipped my bicycles with Garmin Edge computers that recorded location (GPS), speed, cadence and my heart rate. I covered more than 7683 kilometers during 320 hours of riding. It's time to review all the data and share some photos I took along the ride!

Harvesting boredom to let creativity flourish

using the Punkt MP01 dumb phone

Oct. 1, 2016
What does it mean for my state of mind and creativity if I am no longer be constantly connected to the Internet using a smartphone.

Smartphones are everywhere in the modern society we live in today. Through our 4G and WiFi connections the internet is just one tap away. In fact, it is so close that it feels like a natural extension. But is this wealth of information all good or does it have a downside too? It seems like an interesting experiment to go app-less for a while and solely use a dumb phone.

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My bike with Bluetooth sensors connected to my MacBook running Xcode
My bike with Bluetooth sensors connected to my MacBook running Xcode
The experiment is on!
The experiment is on!
Find tasty croissants in Kesteren’s local bakery, Bakkerij de Greef!
Find tasty croissants in Kesteren’s local bakery, Bakkerij de Greef!
You can see the light coming through right next to the disc - nothing is obstructing it and the squeaking noise is gone!
You can see the light coming through right next to the disc - nothing is obstructing it and the squeaking noise is gone!
Refueling at a tank station
Refueling at a tank station
Screenshots of the app's onboarding process: asking for permissions and guiding new users
Screenshots of the app's onboarding process: asking for permissions and guiding new users
Designed to be worn 24/7, the WHOOP strap collects biometric data over a longitudinal period of time - providing you with personalised insights in your health and fitness
Designed to be worn 24/7, the WHOOP strap collects biometric data over a longitudinal period of time - providing you with personalised insights in your health and fitness
Better choices, better health, more fun! (even when it's freezing!)
Better choices, better health, more fun! (even when it's freezing!)
This felt as a fitting place for a little drink stop... Willemsplein in Arnhem!
This felt as a fitting place for a little drink stop... Willemsplein in Arnhem!
My Commuter bike in January 2021 - sharp eyes among you will spot the child's seating mount - as some things do change, ha!
My Commuter bike in January 2021 - sharp eyes among you will spot the child's seating mount - as some things do change, ha!
"Goin' the extra mile": 8 hours on my bike to test battery usage (note: there is still 23% power left!)
I got some magic in my pocket: The app tracking workouts from the background - during recordings it just shows a widget on the homescreen
I got some magic in my pocket: The app tracking workouts from the background - during recordings it just shows a widget on the homescreen
The morning after: Make sure to be kind to yourself - after such an intensive effort your body needs time to recover. My WHOOP noticed this clearly, even after getting a good night's rest.
The morning after: Make sure to be kind to yourself - after such an intensive effort your body needs time to recover. My WHOOP noticed this clearly, even after getting a good night's rest.
HealthFit uses open and well documented formulas to calculate your training load, directing you into a 'sweet spot' to achieve maximum gains while limiting risk of over training
HealthFit uses open and well documented formulas to calculate your training load, directing you into a 'sweet spot' to achieve maximum gains while limiting risk of over training
The day before my departure, I checked my bike thoroughly and even did a little test ride around town
The day before my departure, I checked my bike thoroughly and even did a little test ride around town
Ready, set, GO! Taking part in the Venloop - I am not the only one!
Ready, set, GO! Taking part in the Venloop - I am not the only one!
Training through chilling hail... (Haarlemmermeerpolder)
Training through chilling hail... (Haarlemmermeerpolder)
HealthFit is a fantastic app offering you detailed insights of the workouts you record with your Apple Watch, WHOOP, Garmin, Wahoo or any other app that supports Apple's HealthKit
HealthFit is a fantastic app offering you detailed insights of the workouts you record with your Apple Watch, WHOOP, Garmin, Wahoo or any other app that supports Apple's HealthKit

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