The device to run injury-free.

De Novy applicatie op een smartphone


The greatest fear for running enthusiasts is incurring an injury by putting too much load on their body too soon.

Senne Bonnaerens, Rud Derie, and Kristof De Mey, together as OnTracx, developed a wearable solution that accurately measures the body's mechanical load during running.


OnTracx sought a partner who could match their pace, as they aimed to market their product within four months. We initiated our partnership by conducting workshops to define the MVP's functionalities.

At the beginning of our collaboration, OnTracx was working on an investment round. Together, we developed a visual prototype to aid discussions with investors. By aligning stakeholders both internally and externally, we were able to successfully draw them into the OnTracx narrative, resulting in a successful investment round.

Insights and guidance

The device sends real-time g-forces to the smartphone via Bluetooth, providing athletes insight into their running mechanics. We decided to present this objective data as visually as possible. During a run, a color-coded pulse is real-time displayed each step. When the load is low, it is green, when it becomes higher, the color changes accordingly.

We delivered an updated version every sprint, which OnTracx presented to a panel of runners. This way of working allowed us to keep fine-tuning the concept and work toward launch in four months.

After exercising, runners are presented with a color-coded map of their entire route. This visual aid enables them to identify areas of higher or lower intensity, and relate it to their e.g. running pace or the terrain. The software estimates injury risk, based on both objective loading data and the runner's reported discomfort after each session. It also indicates how much additional load progress they can safely achieve for the current week.

We are delighted with Aaltra because the team always looks for solutions and can respectfully give feedback. The communication was proactive and pragmatic.

Senne Bonnaerens, founder OnTracx

While OnTracx’s proof of concept worked only on Android, we developed a cross-platform application in Flutter. The users' data is securely stored on Hylyght, a paramedical backend platform with great attention to security.

The results

During the initial launch, OnTracx successfully sold 220 devices.

In the next phase, the company plans to continuously improve the application. They will add features based on the needs of the end-users and aim to integrate with other sports applications and devices.

Want to learn more about this case?

Get in touch with Pieter.