Optimize the return-to-run process of your patients.

OnTracx revolutionizes rehabilitation of overuse injuries by managing mechanical load during running.

Take clinical reasoning to an entirely new level

Precision in treatment

Improve the relevance and quality of your treatment plans by leveraging our tools' advanced load management capabilities.

Evidence-based decision making

Make informed, evidence-based decisions for injury prevention and rehabilitation strategies based on the most recent scientific findings.

Enhance patient outcomes

Find out how patients manage mechanical load, running session after running session, allowing you to go beyond traditional rehabilitation strategies.

Add context

Asses how the experienced load relates to pain and comfort, and intervene when necessary.

Knowledge base


The chance you have of
getting injured every year.


The amount of injuries caused by too much load on your body.


Less injury risk if you manage load properly.

Guide patients gradually back to running.

1. The OnTracx sensors

Connect the OnTracx sensor to the lower leg and measure mechanical load in an evidence-based manner. 

2. Real-time data

Check the response of individual changes in running style, footwear, or other (clinical) interventions on patient’s load.

4. Add context

Assess how the progression in load relates to pain and comfort, and intervene when necessary. 

3. Cumulative load

Get a grip on the cumulative load that patients endure when running, both inside and outside the clinic.

5. Share information and educate

Assess how the experienced load relates to pain and comfort, and intervene when necessary. 

Ask for a demo, or join the waiting list. 

We’re currently working with early adopters to optimize our OnTracx PRO product. Can’t wait to test our beta product, or want to know more? Don’t hesitate and ask for a (online) demo!

What (clinical) experts think of it


Training for a marathon

"By using OnTracx I discovered that there’s a real difference in load depending on the terrain I run on. Now, I use OnTracx to map my load during every running session".


Tech-savvy recreational runner

“OnTracx gives you more confidence that you can run to improve your health without jeopardizing it.”


Experienced runner

“I was surprised by how much load my body has to endure during every run, and how much it changes between runs. I now use OnTracx to gradually increase the load week by week, instead of only focusing on running speed and distance.”

Aron Verhaeghe


What I really like is the visualization of mechanical load in such a way that it is easy to understand. Both for me as a professional as for my athletes. I use OnTracx to educate my athletes when it comes down to mechanical loading, and how it relates to the occurrence of overuse injuries.

Jan Victor

Head orthopaedics UZ Gent

Running with lower loads offers long-term benefits in terms of joint health. OnTracx allows you to quantify and subsequently manage that load, and can as such be considered an alternative for knee surgery in patients with mild to moderate knee osteoarthritis.


Currently injured runner

”As a currently injured runner, OnTracx is my ideal running coach. It helps me to understand what my body can handle, so I can keep enjoying my weekly runs. Love it”.


Recreational runner

“Can’t run without it.”

E.C. Frederick

Founder Nike Sports Research Lab

Runners, clinicians and the running industry have needed something like this since forever.


(Start to) runner

”As a data freak, OnTracx is perfect for me. I love to learn more about my body and how it reacts to my training.”



“As a runner who suffered from injuries before, OnTracx provides me with relevant data and insights in order to rehabilitate in an efficient way.”

Sara Waerlop


OnTracx allows me to gradually increase the load my patients experience, in a valid and evidence-based manner. By monitoring mechanical load in combination with pain and comfort experienced by the patient, it allows me to provide better follow-up during the return-to-run process in a very time efficient manner.

Backed-up by science

OnTracx is an award-winning solution. 

International awards

Most innovative piece of running technology (FBS award)

Research awards

Reliable method to track load during running outside lab-settings
(BJSM award) 

Industry awards

High societal relevance & scientific expertise (BiR&D award)

We can imagine that you still have quite some questions. We tried to highlight the most important ones and divided them into different topics of interest:

What does mechanical load mean?

The mechanical load is the load that your muscles and bones (of the lower extremities) have to endure during running.

Mechanical load is very different from the so-called ‘physiological’ load, which represents e.g. your heart rate, your breathing and how much energy your body requires during physical activity. 

When the mechanical load becomes too much for your body to handle, overuse injuries, such as stress fractures, can occur. Although it has been possible to measure physiological load already for a long time (via heart rate belts, running watches, etc.), OnTracx is the first to quantify mechanical load in a valid and reliable way.

Why is mechanical load so important in preventing overuse injuries?

Because more than 70% of all running injuries are caused by too much mechanical load. 

Recent scientific evidence shows that many overuse injuries in running occur when the mechanical load a runner experiences is too high for what the body can handle. However, this load is influenced by a number of factors such as running style, surface and footwear choice. As a result, changes in one of these factors can be detected when taking a look at the mechanical load profile of a runner. 

Studies have shown that the experienced load can be very different between runners, even when running at the same pace. Until now, this load is typically measured on a treadmill in very specialized and expensive lab settings (only covering a short period of time). This makes such analyses very expensive and difficult to translate to a real-world context. 

By using the OnTracx sensor and related algorithms, your load can be measured and subsequently managed correctly every time you go for a run, with the ultimate aim of avoiding (another) running injury. 

How does OnTracx take surface, footwear and running style into account?

Simply put, these parameters can all have an effect on the mechanical load you experience. 

However, these changes are very individual and can thus differ from runner to runner. OnTracx allows you to discover which surface, footwear type and running style have a positive effect (i.e. lower) on mechanical load. In the case of people transitioning during their rehab into a return-to-run phase, the same information can be used to gradually increase the load on their body, while managing the pain and overall comfort levels.

Can OnTracx also be used to measure mechanical load during other activities than running?

Yes that’s possible, but only unidirectional and dynamic movements.  
OnTracx allows you to discover, both as a patient and a healthcare professional, how much mechanical load the muscles and bones of your lower legs endure while performing other (dynamic and unidirectional) movements such as a drop jump, forward jumps, single leg hops, and so on. As a result, OnTracx can be used as an ‘educational tool’ to teach patients what mechanical load is, and to demonstrate how much load a runner/patient endures during running, step by step. 

Did you know that the mechanical load of a single step during a running activity is higher compared to most training drills used in a rehabilitation context?

Why is it placed around only one leg?

Currently this is for practical reasons.

Bilateral load quantification can offer valuable information in the return-to-run process. However, mechanical load can currently only be measured based on one leg (but we’re working on it). We advise you to attach the sensor, during rehabilitation, at the injured leg.

With which smartphones or tablets can I use OnTracx?

It is hard to test all devices out there and bluetooth can sometimes become an issue. However, we keep an updated list of the tested devices right here. If your device is not listed, it does not necessarily mean that it will not be compatible, and it might be interesting to reach out before buying OnTracx.

What does the OnTracx sensor measure exactly?

The OnTracx sensor measures the acceleration of the tibia (or shin bone) during running. 

Scientific research showed that the peak of this tibial acceleration (PTA; this is when the foot hits the ground) is strongly related to the shock or impact measured in the lab. As such, OnTracx allows measuring the impact or shock for every step, in an outdoor setting (where and when it really matters). This allows runners to work on injury prevention based on load measures. In addition to this, we’re also developing more advanced loading metrics. More on that soon!

How accurate is the measurement?

Here it gets a bit scientific, but the correlation between the signal from the sensor and the laboratory measure shows a very strong correlation of r = 0.91. 

This means that our sensor-based measure is almost the same as the load parameter calculated in lab-settings. As a spin-off from Ghent University and its Sport Science Laboratory - Jacques Rogge, we care about the accuracy and validity of our product, and do not aim to create something that looks good but doesn't really do the job. 

Our measurements have been validated with the so-called ‘golden standard methods’. This means that we checked - and verified - that the load measured by Ontracx is similar to the one measured in specialized laboratory settings. This however doesn’t mean that our product is perfect. It just means we’re confident that what we’re measuring is correct enough to be used in real-world settings.

What’s different between OnTracx and other wearable (running) devices?

There are quite some other running tools out there, but they all have a different purpose compared to OnTracx. 

While many other (wearable) technologies focus on how to improve performance, the focus of OnTracx completely lies in the injury prevention and return-to-run areas. We’re one of the first to quantify mechanical load in an evidence-based and reliable way, and translate this type of information to all runners out there, with only one goal: reduce the millions of running injuries worldwide.

Why is it placed around the lower leg?

We strategically placed the sensor on the lower leg because, during extensive testing, it proved to be the most reliable location to measure mechanical load during running. Here's why:

Specificity: The lower leg experiences the first rapid deceleration as your foot strikes the ground. Which only can be captured by measuring at that specific location.

Consistency: Unlike other locations, such as in the shoe, on the laces, or on the lower back, attaching the sensor around the lower leg minimizes interference from external factors and ensures your data reflects actual running load.

Validation: Through rigorous lab testing, we found that the lower leg provided the most accurate and reliable data.

How should you attach the sensor around your leg?

It’s important to place the sensor the same way every time you go for a run. Here are some guidelines for proper sensor attachment:

Place the sensor about 10cm above your inner ankle, on the flat part of your shin bone. Always attach the strap firmly, in a similar way, and on the same leg (we advise to put it on the leg that suffers (most) from running injuries). 

To make this more clear, we made a video that shows you how to attach it exactly!

Why focus on the return-to-run process?

In the return-to-run phase it is crucial that the perceived load on the body is built up gradually and in an objective manner. And this for several reasons:

  1. Since the patient had an overuse injury, this means that the body was loaded too much in the past. As such, the patient cannot simply 'return' to his or her initial state of training.
  2. Exercise therapy has been shown to be effective in avoiding overuse injuries, and is therefore crucial in a rehabilitation context. However, exercise therapy takes quite some time before it becomes effective (up to months). It is therefore imperative to focus on strengthening the body during rehabilitation, as well as identifying and gradually increasing the mechanical load on patients. 

The latter is called 'proper load management', and is exactly what OnTracx offers.

Will patients never get injured again by using OnTracx?

Unfortunately, that’s still possible.

Although most running injuries are caused by an excessive amount of mechanical load, they also depend on a variety of other parameters. This makes it very hard to estimate whether someone will get injured or not, as it is not straightforward to quantify and interpret each of the parameters and their mutual relationships. 

However, knowing the individual load profile of patients can provide valuable information to prevent (re-)injury and to optimize the rehabilitation process. This is because mechanical load is considered the most important risk factor for overuse injuries in running, and should be increased gradually (based on objective data) in a return-to-run context.  

How can you implement OnTracx into your daily practice?

OnTracx gives you the possibility to measure mechanical load in an objective manner, both in the clinic and outside of the clinic. 

This means that OnTracx offers a huge advantage on several fronts during rehabilitation (and mainly during the return-to-run phase):

  • When the patient is ready to start running again, the mechanical load can be objectively mapped from step one. This allows healthcare professionals to gradually increase the mechanical load, and as such not ‘overload’ the patient from the beginning. Additionally, OnTracx allows to explain the importance of mechanical load to patients (i.e. as an educational tool), for whom the concept ‘load’ is often difficult to understand.
  • When running on a treadmill in a clinical practice, the mechanical load can be completely different than when a patient runs outside the clinical setting (just think of the cushioning effect of a treadmill, and the stiff surface of concrete). With OnTracx, the mechanical load during running can also be mapped outside the clinical context (i.e. remote monitoring), in order to provide the patient with even better care, and a better follow-up. 

Is there an ‘optimal’ running style?

Simply put: no, there isn’t.

Current scientific evidence shows that there’s no such thing as a ‘perfect’ running style that every runner should adopt, when it comes down to injury prevention or rehabilitation of overuse injuries. There are two important aspects here to take into account:

  1. The running style of a patient (also called ‘kinematics’) can influence the way his or her body is loaded, BUT… 
  1. … a certain change in running style (for example increasing cadence or step frequency) can lead to a reduction in the experienced mechanical load for some runners, but to an increase for others. 

Changes in running technique can thus be effective in reducing mechanical load, but it needs to be measured (on an individual level) to know this. Here, OnTracx can help in supporting the right intervention. 

For which type of injuries is OnTracx (most) relevant?

Especially tibial stress fractures, plantar fasciitis, Achilles tendinopathy and patellofemoral pain have been shown to be related to a very high variety of parameters of which an excessive amount of load is considered the most crucial one - by far! Based on the available literature, managing load has already been shown to be one of the most effective ways to successfully reduce the number of running injuries. 

Is OnTracx a medical device?

No, OnTracx is not a medical device.

However, our innovative technology is designed to effectively manage mechanical load on the lower legs during running. Although not a medical device, our solution can be very relevant for injury prevention or rehabilitation purposes. Always consult a healthcare professional for personalized medical advice. Please take a look at our terms of use for further details.