Athlete at a glance

Results

Triathlon coaching: the ambition

When Marvin came to me for coaching at the beginning of 2025, his ambition was: “I want to take the next step as a triathlete.”

We had to make that more specific.

Marvin had raced at a high level among elite cyclists for many years. On the bike, he was often among the strongest athletes in the field. His swimming was solid and technically quite well developed.

The biggest opportunity for progress lay somewhere else.

In running.

First understand, then train

As with every new athlete, the process started with an intake and exercise test.

That test provided insight into his physiological profile and showed where the biggest gains could be made.

His aerobic threshold was at 4:58/km and his anaerobic threshold at 4:17/km.

Because his long-term goal was Ironman Cascais, the focus was not on short-term speed.

We first wanted to make the engine bigger. To become more efficient.

After all, a strong aerobic base forms the foundation for both a marathon and an Ironman.

The first sign: Rotterdam Marathon

The winter was largely focused on running development.

Not through extremely hard workouts, but by increasing aerobic capacity and building load capacity.

At the same time, we continued to maintain his cycling.

That was important.

Because the goal was not to turn a cyclist into a runner.

In triathlon coaching, the goal is to grow into a complete triathlete.

That approach resulted in a new personal best at the 2025 Rotterdam Marathon: from 3h23 to 3h14.

Running faster while continuing to ride strong

After Rotterdam, the focus shifted back towards triathlon.

Cycling took a more prominent place in the programme, while we continued to build on the running level he had developed.

At the 2025 Westland Triathlon, this resulted in a bike split of 56 minutes and a run split of 41 minutes.

A strong foundation for the rest of the season.

More importantly, it proved that the extra focus on running had not come at the expense of his cycling level.

Ironman Cascais

The preparation for Cascais revolved around further increasing his load capacity on the bike and during the run.

All of this had to fit within the reality of a busy life as an entrepreneur and father.

That is exactly where an important part of personal coaching lies: developing a training programme that does not only work on paper, but is also feasible in practice.

In Cascais, that resulted in a finishing time of 9h43.

What stood out most was his 3h27 marathon.

Only 13 minutes slower than his standalone marathon in Rotterdam earlier that year.

A clear sign that the aerobic development was paying off.

The second step: running more efficiently

After Cascais, we took the next step.

Not just more running volume.

But also more attention to running technique.

The data showed that Marvin had a relatively low cadence. That came at the expense of his running efficiency.

By working specifically on cadence, running posture, and efficiency, new room for progress was created.

Triathlon coaching: the reward

The next performance test showed that the development was not only visible in races.

Physiologically, major steps had also been made.

His aerobic threshold improved from 4:58/km to 4:27/km.

And his anaerobic threshold from 4:17/km to 3:49/km.

Shortly afterwards, a new marathon PB followed: 2h56 in Rotterdam.

An improvement of 27 minutes compared with his level at the start of the process.

And one month later, Marvin won the Westland Triathlon.

This is how he improved compared to the previous year:

• 1 minute faster swimming
• 1 minute faster cycling
• more than 5 minutes faster running

The best result

The best result was that this gain was not achieved by further developing his strongest discipline.

But by purposefully developing his weakest discipline.

That is how Marvin developed from an elite cyclist into a complete triathlete.