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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!

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Flyer announcing the play
Flyer announcing the play "Zusters in Zaken" by "De Opregte Amateur"
The mechanical disc brakes have no trouble stopping you
The mechanical disc brakes have no trouble stopping you
Bluetooth scan from the 4iiii app
Bluetooth scan from the 4iiii app
Around the Markermeer, through the former Dutch
Around the Markermeer, through the former Dutch "Zuider Zee"
Wahoo TICKR, waist worn strap, measuring heart rate in realtime
Wahoo TICKR, waist worn strap, measuring heart rate in realtime
Apple Watch has an optical heart rate sensor, cleary visible in the middle of the underside
Apple Watch has an optical heart rate sensor, cleary visible in the middle of the underside
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
The bike features a sporty city steer and an integrated touchscreen in the frame
The bike features a sporty city steer and an integrated touchscreen in the frame
Different strap styles and lengths
Different strap styles and lengths
Quad Lock smartphone mounting system
Quad Lock smartphone mounting system
My 'bike area network': sensors (red) and displays (green) connected to the smartphone
My 'bike area network': sensors (red) and displays (green) connected to the smartphone
Home sweet home! 211 incredible kilometres!
Home sweet home! 211 incredible kilometres!
Smiling at the Markermeer
Smiling at the Markermeer
Wim Hof in ice blocks wearing sensors
Wim Hof in ice blocks wearing sensors
The booster button, conveniently positioned near the left thumb
The booster button, conveniently positioned near the left thumb
Holding my son for the very first time - trying to make sense what the little man wants... (a recurring theme as I would find out)
Holding my son for the very first time - trying to make sense what the little man wants... (a recurring theme as I would find out)
Looking over the Markermeer at the (former) island of Marken
Looking over the Markermeer at the (former) island of Marken
You should be able to loosen the plastic cap with just your fingers/hand, no extreme torque is required
You should be able to loosen the plastic cap with just your fingers/hand, no extreme torque is required

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