7.5 Years of Running Secrets

7.5 Years of Running Secrets

Ron and Hans during a Netherlands Championships Masters at the Utrecht athletics track Maarschalkerweerd

This week is was 7.5 years ago when the first article by Hans and Ron appeared on ProRun. Since then they published a new article every week. With explanations about aspects that affect your running performance or with good analyses of current sports performances.

Hans and Ron’s scientific approach uses the laws of physics and physiology. Most of their articles have been published in ProRun. Nevertheless, you can also find them regularly in other Dutch and international running magazines and running sites. Meanwhile, they have published 500 articles.

How did it start?

Hans started running in 1980. On the day Dutch runner Gerard Nijboer took Olympic silver in the marathon in Moscow. In his teens Hans had played soccer in Feyenoord (Rotterdam) and he also appeared to have talent for running. Ron had contracted the running virus a few years earlier.

Together they became colleagues, they are lifelong friends and above all lifelong runners. With Sunday morning as a fixed moment for their long run together. They discuss the experiences of the week and make new plans during these runs. Over the years they have trained more than 40,000 km together and have run races or trainings in beautiful places worldwide.

A busy job and family life meant that over the years the emphasis got less on performance and more and more on recreational running. Until 2011. When he retired early as professor at Delft University of Technology, Hans was given a Garmin watch with a heart rate breast band by his students. Hans had not used anything like that before as he ran by feel. Ron already had a running watch, but used it only to see his courses afterwards. His heart rate breast band remained unused.

In the long Sunday runs through nature, Hans’s new watch quickly became the topic of conversation. They noticed numerical relationships between pace and heart rate. Engineers love numbers so they delved into the theory. With themselves as a test object, they were able to confirm the relationship between pace and heart rate and many other relationships.

Because of the busy social life, they had gained some body weight. This quickly led to confirmation that losing 1% of weight leads to being 1% faster. If you go on a diet and lose 15%, like Hans did in 2012, you run 15% faster. The profit of more targeted training can be added to that.

Ron started running the same times as he did in the early 1990s. Hans competed in his age group both on the road and on track for the Dutch national titles. The fun and passion also led to achievements at international tournaments.

Hans in the silver 5000 meter final M55 between the Russian combine of Alexandre Kaplenko (207) and winner Leonid Tikhonov (1120) during the World Masters Games in Turin (2013)

The Secret of Running

A lot of running literature was reviewed, tried out in practice and discussed with experts. They also analyzed the performance of top athletes and recorded and documented everything. The basis of the book The Secret of Running was laid.

The first Dutch edition was published on 13 October 2013 and proved to be a bestseller. That was certainly also the case for the calculator on the website www.theSecretofRunning.com. Still, hundreds of runners each day visit this website to calculate the impact of the conditions on their running performance, or to have the time calculated at a different distance, in case of wind, height differences, altitude, other surface, low or high air pressure, the impact of aging and much more.

The many responses ranging from typographical errors, even more information and experiences, and substantiations led to an even better second edition in April 2014. This one is still for sale as an e-book.

The Secret of Cycling

The accessibility of the book The Secret of Running with the many short chapters in which only one aspect is explored led to the question of writing The Secret of Cycling.

Hans and Ron are cycling enthusiasts, but were not practicing and did not have a network in this branch of sports. Sports doctor and cycling coach Guido Vroemen was able to fill that gap sublimely with his broad experience and expertise. In June 2015, The Secret of Cycling rolled off the presses. As an e-book,  this standard work is still widely sold.

Cycling and running have many similarities as endurance sports. The use of power meters is very common among performance-oriented cyclists of any level. Power (wattage) is no more or less than the amount of energy you consume per second (kiloJoules (kJ) or kilocalories (kcal)). With the law of physics you can calculate the rolling resistance (tires, road surface), air resistance (wind), climbing resistance (slopes) and mechanical resistance (chain, gears). This resulted in the cycling model. On www.theSecretof Cycling.com, everyone can calculate the impact of all kinds of aspects on cycling performance with the calculator.

The eye opener was that basically this cycling model is also suitable for running and other endurance sports like speed skating. These sports all are related to the same laws of physics and physiology. Speed skating is of course about sliding resistance instead of rolling resistance. When running you do have slopes and no losses due to chain and gears. The universal calculation model for endurance sport was born.

Basically, cycling and running are related to the same laws of physics

Running power

With the insights gained in cycling into the concept of wattage (power), it naturally came to mind how beautiful it would be if you could also work with power when running. Hans dived in the theory and perfected the running model with power.

Never before has running performance been so perfectly calculated, evaluated and performance predicted. All this was elaborated in the book The Secret of Running.

There was only one problem. Running power meters did not exist. You could calculate wattages but unlike cycling you could not measure it while running.

Coincidentally, Hans and Ron came into contact with kickstarter Stryd. This company, based in boulder, Colorado, came on the market with a running power meter.

Soon contacts were made and an inspiring substantive e-mail exchange arose. At one point, the current Stryd CEO Jamie Williamson even came to Amersfoort (the Netherlands) for discussions, testing on the athletics track and performing exercise tests in the laboratory at SMA Midden Nederland.

One and one is two. With the theory from The Secret of Running and the practice of the wattages that Stryd measures came a world of opportunities to look at running performance. The small footpod on the lace of your shoe is extremely accurate. The instruments in the device measure movement hundreds of times per second. Speed, distance and height differences are therefore many times more precise than any GPS watch.

The Stryd running power meter attaches to the laces on your shoe and connects to your Garmin, Polar, Coros, Apple Watch or other sports watch

Initially, Stryd measured only the running resistance and climbing resistance. With an ingenious system, it now also measures the air-resistance. Stryd uses a measurement principle similar to the pitot tube known from flow theory. Stryd calls it a “wind port”. Hans and Ron know pitot tubes from their water background. In the aircraft industry, this measurement method is commonplace for measuring flight speeds. Hans and Ron were a bit sceptical at first. Stryd then gave Hans and Ron the opportunity to test it themselves in the wind tunnel of the Netherlands Aerospace Centre (NLR) in Marknesse. And there they became impressed and convinced.

Still not everyone in the athletics world takes the Stryd seriously. Running power is determined differently than with the direct measurement of power from the force on the pedals of a bicycle. Some don’t think the algorithm-calculated Stryd power is a real wattage. This category of people will also have problems with the speedometer in their car’s dashboard. This speed has not been determined mechanically in years.

A big advantage of Stryd’s wattages is that they match the values cyclists know from their power meters. Triathletes and duo athletes can work better with this than with the higher gross power values of Garmin Running Power and Polar Power.

And the most important advantage is that with the Stryd values you are independent of the conditions during training or competition.

Hans checks Stryd’s test setup in NLR’s wind tunnel. On the treadmill runs Ray Maker (DC Rainmaker)

Red Thread ProRun

In the meantime, the weekly publication of articles at ProRun continued. For example, Hans and Ron have shown under which (unregulated) conditions a marathon under two hours is possible. Of course, they analyzed Eliud Kipchoge’s attempt in Monza (Italy) and his success at the INEOS 1:59 Challenge in Vienna. With a tail wind on the Afsluitdijk (32 K closing dike in Lake IJssel, the Netherlands) it would also have been possible.

Of course, they also studied Nike’s new shoes that deliver better running performance. Similar to  what happened in speed skating when the clap skate was introduced.

They also explained how great the leading group in the Standard Chartered Dubai Marathon 2020 worked together to the end, keeping each other out of the wind and ended up with 11 runners under 2:07. Between numbers 1 and 11 there were only 19 seconds. Of the 20 first finishers, 14 ran a PR.

How about the Andalusia marathon, the fastest marathon in the world with a height difference of 1938 meters and finish in Malaga. That was fast but also accompanied by injuries. The speed gain from the continuous decline of the course resulted in stress on muscles, tendons and knees.

Everyone knows that running performance decreases with the years. It’s nice to know how much less that is and how fast you would have run at 28 years with your current form. It motivates Dutch masters to continue.

Hans and Ron also evaluated the performance of cyclist Tom Dumoulin in the Tour de France. What difference does a kilo of body weight make? And many articles came along about the influence of temperature on running performance, sweat production and the limits of human performance.


The success of Hans and Ron’s books and articles did not go unnoticed. The Secret of Running and The Secret of Cycling was picked up by Meyer&Meyer, the largest European sports book publisher. The books are available worldwide in English, German, Spanish and Italian. This is also reflected in the visit to the bilingual website www.theSecretofRunning.com.

On this webpage you can find a nice overview of all editions and appearances of the books.

Global interest for the information and calculator at www.theSecretofRunning.com

The Fastest Way to A PB: Running on Power

Is this the end? No, definitely not! A new book is now in the pipeline. The writing was done by Koen de Jong this time. The book is intended for a wide audience and the Dutch edition will be published in the second half of March 2021. English will follow soon and after that Spanisch, German and French. More languages are taken in option.

Wide audience? In the foreword Koen indicates that he wrote it in such a way that anyone who was happy to get rid of science in high school can follow and use it.  After all, you don’t need to know how your car’s speedometer works to keep you up to speed. And if you also see on your dashboard how far you can go with your fuel tank, you know whether or not you will reach your destination without refueling. This way you can indeed use the Stryd running power meter too.

So you want to read more about running on power? Then you can request the book The Fastest Way to a PB: Running on Power by Hans van Dijk, Ron van Megen and Koen de Jong as e-book (free) via ProRun (Dutch edition). This e-book is available in the second half of March 2021. At the end of April 2021, the book ‘The Fastest Way to a PB: Running on Power’ (Dutch edition) will also be published in printed form, with ISBN 978-90-821069-5-4. It is for sale at the regular bookstore for 10 Euro’s.

We are happy to announce that this book also goes international. An English edition will be published this spring. Followed by Spanish, German and French. An option has been taken on other languages.

You can find out more about this new book via this link.

Passion and Pleasure in running are at the heart of this new book. Koen de Jong, Ron van Megen and Hans van Dijk explain to the reader how you can easily achieve better Performances.

Is this the end?

No, certainly not. Hans and Ron are definitely continuing. They find it very inspiring to develop new applications. Of course, Stryd will have to pick that up themselves. That’s not what Hans and Ron are about.

Just last week they asked an experienced marathon skater to test the Stryd in speed skating. In theory, that should be possible. In practice, a clap skate is never detached from the ice and the algorithm lacks a signal. Something like that seems very soluble.

From the sports doctor of a soccer club in Montevideo, Uruguay, came a question about the applicability to football. Now GPS is widely used for the movements of a soccer player in the field. No matter how good the GPS system is, it’s always slow compared to a soccer’s movements and the kicks against the ball. A Stryd can keep up with this. You could then attach it to the heel of the football shoe. One problem is that the people of Stryd do have a scientific staff and network that has been experience in running, but high-level soccer is a profession in its own right.

We also liked an Englishman’s questions about the idea of attaching a Stryd to a horse’s legs in horse racing.

We can go on like this for a while. And we will!

Our book ‘The Secret of Running’ is for sale in our webshop. Also available in German as ‘Das Geheimnis des Laufens’, and in Italian as ‘Manuale completo della corsa’.