My UM
My UM
Search

FieldLAB: measuring stress where it actually happens

Chronic stress is often invisible until its consequences become impossible to ignore. It shows up as exhaustion, errors, chronic health problems, irritability, or people quietly quitting their hobbies or even leaving their profession. In high-stakes environments, leaders are expected to remain calm under all circumstances. Often, they do. Yet maintaining that composure comes at a cost. This blog article draws on four years of research within the FieldLAB project, conducted at Maastricht University in close collaboration with international partners, such as the ACDC Lab in Houston. The FieldLAB team followed emergency physicians, special police forces, and crisis leaders into their operational environments. The goal was straightforward but ambitious: to understand how stress unfolds outside the laboratory, and how this knowledge can be used to design better biofeedback, improve training, and help professionals build stress awareness as a key competence for long, sustainable careers.

Why This Research Matters to Me / Corinna

My interest in stress is deeply personal. Before academia, I was a nurse. In emergencies, staying calm wasn’t a skill; it was a core competence. While working at a hospital in Aachen during COVID, I experienced constant pressure and growing exhaustion. Stress was not only a theoretical concept I studied at UM, but a daily reality for our team, but at which cost? Reality hit after the sudden loss of a crisis leader in Limburg. It forced an uncomfortable realization: the people who steady everyone else in the worst moments often carry their own burden unseen. I missed that perspective, too. Back then, my ward manager Nadja felt like a rock, strong, sharp, endlessly empathetic, always keeping the good spirit up. Looking back, I wonder how she was really doing during the pandemic’s adversity. Placing crisis leaders like Nadja at the center of my PhD was never just an academic decision. After the pandemic, it felt long overdue, almost like a responsibility. One that I carry, but one we also share: as organizations, as communities, and as researchers at UM. 

When we started the first FieldLAB studies, one thing became obvious: despite the chronic stress levels the issue was never a lack of performance, motivation, or commitment. If anything, it was the opposite. These leaders push themselves relentlessly. What they struggle with is stepping back, realizing how much strain they are carrying, noticing when their body is still stuck in “crisis” mode, and allowing themselves to recover. Every participant came with a unique story, different pressure points, and different resources. Even those leaders who appeared unshakeable felt the quiet toll of chronic stress. Understanding how to help team leaders recognize their own stress, recover more effectively, and stay healthy while doing work that truly matters is what drives this research forward.

Why Continuous Physiological Monitoring Matters and Why Stress Doesn’t Live in the Lab

Much of what we know about stress comes from laboratories. In many stress studies, people sit still in a laboratory, wear sensors, and react to carefully designed tasks or imagined scenarios. The setup is controlled, the stress induction is thoughtful, and the data is clean. But real life doesn’t follow a protocol. Real stress unfolds across long shifts, night calls, tense team moments, and decisions that carry real consequences. As long as stress research stays confined to the lab, we only ever see part of the picture. For leaders, this gap is especially striking. The people in our studies are not just professionals; they are also parents, partners, and friends. They carry responsibility for others while managing multiple, overlapping demands of their own. Their stress doesn’t appear in a single spike; it builds, lingers, and often follows them home. This realization led to a simple but uncomfortable question:

Can we bring rigorous physiological science into real life without losing meaning in the messiness?

FieldLAB was our attempt to answer that. Instead of observing people for minutes in controlled settings, we followed each participant across four very different days: one high-pressure mission day, two regular workdays, and one day off. We used wearables to continuously track physiological signals, GPS to understand movement and activity, short daily check-ins, and long one-on-one conversations at the end of each monitoring period. The aim was not just to measure stress, but to understand when, where, and why it emerged.

During the debriefings, participants walked through their day, step by step, while examining their own physiological stress patterns. Together, we connected physiological changes, as reflected in their heart rate and heart rate variability, to real moments: a critical decision, an interruption, a conflict, a short pause that mattered more than expected. Over time, this approach generated millions of labeled data points from people working in genuinely high-stakes environments. But the heart rate data was never the centerpiece. Meaning always emerged through dialogue, grounded in lived experience.

FieldLAB did not stay in one place. The research followed professionals from Limburg to Switzerland and into real operational settings. Through close collaboration with Swiss partners, supported by the ZwitserNet network, the work extended to events such as the World Economic Forum in Davos, one of the few places where global pressure becomes visible in real time.

This year in particular, that pressure is hard to miss. As international conflicts dominate the headlines and high-profile figures such as Donald Trump attend the forum, political, economic, and security tensions stretch far beyond the meeting rooms. Even from our living rooms, watching the news, many of us can feel it: a world under strain, shaped by uncertainty, conflict, and constant urgency.

Davos makes this collective stress tangible, not only for those working on the ground, but also for the wider public following events as they unfold. Measuring stress in such frontline contexts shows how complex and unpredictable real-world research can be. Yet it also underlines why it is necessary: if we want to understand how people cope under extreme pressure, and how technology can meaningfully support those responsible for safety and security, we have to study stress where it actually happens.

Importantly, continuous physiological monitoring did not replace personal experience. It complemented it. Seeing stress patterns aligned with real events often made difficult conversations easier. Stress was no longer framed as a personal weakness or failure to cope, but as a measurable response to sustained demand. That shift mattered. It reduced stigma, created shared language, and opened space for more honest reflection about stress peaks, recovery resources, general workload, or support.

WEF
Picture 1: A glimpse into FieldLAB’s real-world context: security forces on duty during the World Economic Forum in Davos. Here, pressure is not simulated but lived, shaped by global tensions, high-stakes decisions, and constant vigilance.

Making the Invisible Visible

“I knew my job was stressful. I just didn’t realize how constant it was.”

That sentence came up again and again in FieldLAB. We didn’t simply hand people a wearable and collect numbers. By tracking heart rate, we followed them through ordinary and demanding days: during commutes, emotionally charged meetings, brief moments of calm, and finally into sleep. The real turning point came later, when we sat down together and looked at the data.

On the screen, the curve told a story many had never seen before. Heart rate rose and fell across the day. Beneath it, the body’s stress and recovery systems shifted back and forth, showing when the body was in “on” mode, bracing and alert, and when it finally had a chance to switch off. Pressure and relief, visible side by side.

For many participants, this was the first time stress felt tangible. No longer a vague sense of being “busy” or “tired,” but a clear pattern. People recognized moments immediately: “That spike, that was the emergency call.” Or, just as often, “I thought I was resting here, but my body clearly wasn’t.”

What made these moments powerful wasn’t the technology alone. It was the conversation. Seeing physiological signals alongside personal memories helped reframe stress—not as a personal weakness or a failure to cope, but as a natural response to sustained demand. For many, that realization changed how they thought about recovery, limits, and what it really means to be strategic about human performance.

HRV results_Corinna Rott.png

What We Learned Along the Way

Across participants, stress had its own signature, unfolding unevenly across the day. On mission days, it slowly piled up. Recovery moments were rare, decisions became heavier, and leaders carried not only their own workload but also the responsibility for their teams' emotional climate. What surprised many participants most was where stress showed up. Days off were not always restorative. Some of the highest peaks occurred in private moments: during family conflicts, caregiving responsibilities, and the constant mental load of parenting. Even when nothing dramatic happened, the responsibility of being “on” for others quietly accumulated in the background. Long commutes added another layer. Driving, in particular, emerged as a hidden stressor. Not physically demanding, but cognitively and emotionally draining and often underestimated until the data made it visible. So, what are the common antidotes to stress? Repeatedly, two things stood out: good sleep and regular, moderate movement. They didn’t remove stress, but they made it easier to carry.

From Insight to Impact: The Future of FieldLAB

One of the biggest challenges in real-world stress monitoring is separating mental strain from simple movement. A racing heart can mean pressure, or just climbing stairs. Without context, stress quickly becomes misclassified. That’s why FieldLAB always interpreted physiological signals in relation to daily activities. When context was ignored, even advanced models quickly broke down. This also explains why many consumer stress apps lose credibility when everyday movement is labeled as stress; people stop trusting the “stress scores” or “Biobattery scores” as feedback.

What FieldLAB ultimately taught us is simple: biofeedback only works when it fits real life. If feedback breaks down in traffic, family chaos, or sheer training exhaustion, people stop trusting it. The aim was never to react to every heartbeat, but to recognize patterns that actually matter, patterns that support recovery, help people plan ahead, and allow them to lead without constantly running on empty. As FieldLAB grew, the focus naturally expanded from individuals to teams. Stress is rarely contained within one person. In high-stakes environments, it spreads, synchronizes, and is regulated collectively. Understanding these shared dynamics is crucial not only for theory but for designing tools that genuinely help teams function under pressure.

These insights now guide where the work is heading. Together with designers and engineers, such as Pauline van Dongen and Touchwaves, which recently received major funding to advance smart textiles for NATO, FieldLAB is moving from observation to creation (see picture). At the same time, we are testing adaptive biofeedback applications developed by the ACDC Lab Houston. Together, these collaborations allow us to turn measurements into design prototypes that can be tested, questioned, and improved.

One lesson from our design workshops with practitioners has stood out across all prototype iterations: do not interrupt performance. In high-stakes situations, attention belongs fully to the task at hand. Reflection comes later. This insight has reshaped how we think about biofeedback in demanding environments. The future of stress technology is not constant alerts or real-time nudging. It is thoughtful, context-aware feedback that supports stress awareness, recovery, and resilience over time through post-mission reflections, weekly summaries, and personalized thresholds that adapt to real lives. Good technology does not demand attention. At its best, smart wearables and biofeedback blend quietly into everyday routines, helping people make sense of pressure after a mission and to engage in suitable recovery strategies to return back to routine the next day.

FieldLAB has always been a collective adventure. From day one, it has thrived on international teamwork and a spirit of shared curiosity. As a ZwitserNet Fellow, I am part of a vibrant network linking researchers from Switzerland and the Netherlands, sparking the exchange of ideas, methods, and real-world insights. This spirit of collaboration is vital when exploring something as intricate and deeply human as stress in professional life. FieldLAB demonstrates how these cross-border connections can come alive in research at Maastricht University and ripple outward.

Pauline Van Dongen Smart Wearbles.jpeg

As FieldLAB moves forward, the questions grow broader and more pressing. How can stress data genuinely support learning, leadership, and performance across different fields? And how can smart textiles and biofeedback tools be designed in ways that are ethical, human-centered, and supportive rather than intrusive or overwhelming? These are the questions I will continue to explore as I enter the next phase of my postdoctoral research at Maastricht University. But they are not questions to be answered in research silos or isolation. FieldLAB remains an open invitation: to researchers, designers, engineers, practitioners, and partners well beyond the university to contribute ideas, challenge assumptions, and help shape technologies that truly support people under pressure. This is where the conversation continues.

Author: Corinna Rott & Barbara Timmermans

Also read