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Sport 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?

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.

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?

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.

Repairing a Giro AEON bicycle helmet

How to replace the Roc Loc 5 system

July 9, 2020
Try fixing your Giro bicycle helmet? I went through some trouble to do it! Read along to find out how.

This month my trustworthy Giro Aeon bicycle helmet broke down! Normally I wouldn't hesitate to invest in safety and thus buying a new one. But I like the Aeon helmet so much that I went through some extra trouble to fix it. Read along to see how I did it.

Minimalistic road bike with Gates carbon drive

Meet your new therapist: the Schindelhauer Siegfried Road

Apr. 30, 2020
For the past few months I have been riding the Schindelhauer Siegfried Road bike with the Gates CDX Carbon Drive, read about this beautiful minimal bike in this post.

For the past few months I have been riding a special kind of bike, the minimalistic Siegfried Road from Schindelhauer. It is unlike most road bikes as it lacks a conventional chain and derailleur. It features the Gates CDX carbon drive. It's an exercise in minimal design. After riding it for nearly 1000KM, it's time to tell you all about it.

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.

Creating a minimal road bike

Recombining and refinishing old parts into a new bike

Aug. 18, 2019
I wondered how hard it would be to make a bike from spare parts I had in my garage

Over the past months I have worked on different bikes, leading to an accumulation of spare parts in my garage. I wondered how hard it would be to make a new bike using these spare parts. I decided to take advantage of this moment to refinish some parts, removing excessive decals in order to create a minimal looking road bike.

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.

Assembling a cargo bike

Setting up the Babboe Big cargo bike

June 25, 2019
How hard can it be to assemble a cargo bike? This posts shares my experience with assembling the Babboe Big cargo bike.

This month our Babboe Big cargo bike arrived, in boxes. The engineer in me thought it was a good idea to assemble the bike by hand. This way I would know exactly about all its parts and fittings, handy knowledge for maintenance. Read along for my experience and some practical 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?

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.

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!

Beast of the Green Hell

Driving the Mercedes-AMG GT R

May 31, 2017
Blog post about an amazing AMG Circuit day at the race track of Zolder, Belgium.

This month I received an invitation to join Mercedes at the Zolder circuit in Belgium to drive in "the beast". The Mercedes-AMG GT R, a furious green coloured performance car that gets its nickname from the Nürburgring where it was developed. It was an incredible experience, well worth a blog post!

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!

Batavus Champion bike from 1978

restoring retro glory with some help from the Internet

Sep. 3, 2016
Restore the retro glory of an old bike from the 70s using the internet.

Almost a year ago I bought an old steel racing bike from 1978. I wanted to figure out if using a bike to commute worked for me. It did! I used it to ride more than 1000KM before I decided to get a modern road bike. Now, almost a year later, I decided to put the powers of the internet into good use: to bring the bike back to its retro glory!

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The pump fits well and I also managed to find a period correct plastic drink bottle
The pump fits well and I also managed to find a period correct plastic drink bottle
Riding my bike as workout (photo by Niels)
Riding my bike as workout (photo by Niels)
Removing the old padding is easy, just detach the velcro tape
Removing the old padding is easy, just detach the velcro tape
This image sums it up, it is my
This image sums it up, it is my "endgame" face - a 42K Marathon finisher!
Installing the cassette is easy if you align it to match the rear axle's pattern
Installing the cassette is easy if you align it to match the rear axle's pattern
Glueing the Roc Loc 5 - bad idea
Glueing the Roc Loc 5 - bad idea
At around 25K there are fewer happy faces around you - people are fully focussed on their effort - it gets serious
At around 25K there are fewer happy faces around you - people are fully focussed on their effort - it gets serious
Let's play the game
Let's play the game "Where's Willem?" :-)
Most parts have torque values written on them in Newton Meter (Nm)
Most parts have torque values written on them in Newton Meter (Nm)
The Babboe Big, in boxes
The Babboe Big, in boxes
Use a crank tool to remove the crank (Shimano TL-FC16 / FC-M960)
Use a crank tool to remove the crank (Shimano TL-FC16 / FC-M960)
Make sure the battery is installed and the covering door is locked
Make sure the battery is installed and the covering door is locked
Rear of the helmet, note how the strap goes through the Roc Loc 5
Rear of the helmet, note how the strap goes through the Roc Loc 5
The Alexrims CX30 silver high polished wheels have high quality hubs ensuring a smooth ride
The Alexrims CX30 silver high polished wheels have high quality hubs ensuring a smooth ride
Using filler plates to make up for Chinese Precision
Using filler plates to make up for Chinese Precision
The Roc Loc 5 broken in my Giro Aeon helmet
The Roc Loc 5 broken in my Giro Aeon helmet
Nothing makes you feel alive like going outside for some physical action - I love working out!
Nothing makes you feel alive like going outside for some physical action - I love working out!
The Schwalbe Marathon Plus Tour tires are very reliable
The Schwalbe Marathon Plus Tour tires are very reliable

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