Why England-Colombia World Cup Match Triggered Apple Heart Rate Alerts

In the waning minutes of a knockout-round game against Colombia on Tuesday, the English national soccer team was clinging to a 1-0 lead when something alarming happened, both for the players on the field and for viewers back at home. As it became clear that England would have to play extra time, people all over the country began to get alerts from their Apple watches warning them about spikes in heart rate as 120 beats per minute.

As The Independent reported Wednesday, some fans received the following message: ”Apple Watch detected a heart rate that rose above 120 while you appeared to be inactive during the 10-minute period”. Some of those fans took their data to Twitter, showing what a bit of sports-driven adrenaline can do.

In a previous interview with Inverse, Dr. Patrick Valcke, a third-year anesthesia resident at the University of Saskatchewan, explained how stress causes a sudden spike in heart rate:

[Heart] rate is typically controlled by two subcategories of the autonomic nervous system. One of these systems, the sympathetic nervous system — also known as the “fight or flight” system — is stimulated when someone is either in the midst of a dangerous experience or has triggered memories of a previous trauma. This feeling of impending danger initiates the release of adrenaline and noradrenaline into the cells that enervate the heart, resulting in a higher heart rate.

While we don’t know exactly how the alerts matched up with the spikes in heart rate, it’s fair to assume that the stress of the game generally stimulated the sympathetic nervous systems of the fans. It might have done so by triggering an anticipatory feeling of stress, brought on by the memory of games past.

This is not, after all, the first time people have reported that watching the English national team play was enough to precipitate a full-fledged biological stress response. In 1998, England was eliminated from the World Cup in a eerily similar situation: a penalty kick shootout against Argentina at the exact same stage in the tournament. As it became clear that England would have to play extra time in Tuesday’s match, England fans may have sensed danger yet again, something that research published in BMJ Open Sport and Exercise Medicine in 2017 suggests might be enough to trigger an “anticipatory” stress response.

While it’s well established that “acute stress” (like life-threatening danger) can prompt the release of hormones that trigger a physiological response, there is a growing body of research showing that anticipation of a stressful event — like a repeat of the 1998 World Cup loss — can also trigger a fight-or-flight response. The authors of the 2017 paper investigated the anticipatory stress response by performing a meta-analysis of 25 previous studies that measured levels of cortisol in athletes before competition. They wanted to see whether just the idea of a stressful event would be enough to produce a spike.

A spike in cortisol in athletes’ saliva before competition, they wrote, would support the idea that “psychosocial stressors” can have as strong a biological effect as actual danger. They found that there was a “significant anticipatory cortisol response before competition,” although the spikes weren’t as strong as those seen before other intense events, like skydiving. Also, notably, they only noticed statistically significant spikes in the saliva cortisol levels of male athletes, which the authors admit requires further investigation.

Their research highlights the idea that just the idea of impending doom can be enough to flood your body with enough of the stress hormones that serve to raise heart rate. And with England’s recent world cup history — notably, failure to emerge from the group round in the last World Cup — it’s no surprise that Apple watches all over the nation picked up on some deep-seated hormonal turmoil.

When England plays Sweden in the quarter final, it might be best to take the heart rate monitors off.