What the wearable World Cup study is trying to measure
The wearable World Cup study is a large-scale research project that uses smartwatch and fitness tracker data from football fans to quantify how emotional match moments affect heart rate, stress, sleep, and daily activity in real time across many countries. Led by Bielefeld University’s QUAMU research area, the project asks volunteers to share data recorded automatically while they watch games, so scientists can see how tension, joy, and frustration show up in the body. Instead of short lab experiments with small groups, researchers are building a global dataset that covers different teams, time zones, and viewing habits. They are interested in what happens during goals, penalties, near misses, and shock results, and whether these events leave traces in sleep patterns and activity levels afterwards. In effect, everyday entertainment becomes a living laboratory for smartwatch sports emotions.
How fans can join and what data their wearables share
To take part, fans sign up through Bielefeld University’s project site and, if accepted into a supporter group, connect their wearable account following the instructions sent by the research team. The study has grown from a Garmin-only trial into a broad citizen science wearables project, now compatible with Apple Watch, Google Pixel Watch, Samsung Health devices, Garmin, Fitbit, Oura, Polar, Amazfit, Coros, Whoop, Xiaomi Mi Fitness, Withings, and Wahoo wearables. Once connected, participants contribute heart rate football data, device-calculated stress indices, sleep information, and activity levels. They can also add optional details about how they watched a match, such as whether they were in a stadium or at home. Data are used anonymously and handled under personal data protection rules. You do not need to watch every game; even a handful of matches can provide useful signals for the researchers.
From living room drama to physiological patterns at scale
Researchers are interested in how real-world football emotions drive measurable reactions, beyond what fans say they feel. By comparing time-stamped match events with smartwatch sports emotions data, they can see how heart rate spikes around goals, penalty kicks, clear chances, or unexpected defeats. Earlier work by the same group during the 2025 German Cup final found that fans in the stadium averaged 94 beats per minute, while those watching on television averaged 79 beats per minute, with heart rates among stadium fans rising by up to 36% after goals. The current wearable World Cup study aims to test such effects at much larger scale, covering many teams and viewing settings. Because devices also track sleep and daily movement, scientists can ask whether high-stress games disturb rest or change next-day activity, painting a fuller picture of how sport shapes the body.
Citizen science wearables: when fandom becomes research
A key feature of this project is how it turns fans into active contributors to science. Supporters are grouped by team so researchers can compare different fan bases, from heavily followed sides to those with smaller but passionate communities. Participation remains open during the tournament, and records from isolated games are still considered valuable, especially from underrepresented regions. According to Bielefeld University, the wider the mix of smartwatch brands, teams, and fan locations, the stronger the analyses of sports emotions become. The study also shows how consumer technology can bridge everyday life and academic research: devices designed for fitness and wellness are now feeding into serious questions about stress, excitement, and recovery. For fans, taking part offers a new way to be involved in the tournament: every rushed heartbeat and restless night becomes data that helps explain why football feels so intense.
