Core Viewpoint - The article discusses the inaccuracies of stress monitoring by smartwatches and apps, emphasizing that the data they provide may not accurately reflect users' psychological stress levels [6][55]. Group 1: User Experiences - Many users have reported discrepancies between their perceived stress levels and the readings from their smartwatches, indicating that the devices may not be reliable [9][54]. - Instances include users feeling relaxed but receiving notifications of high stress, suggesting that the devices may misinterpret physiological signals [13][46]. Group 2: Measurement Methodology - Smartwatches typically measure stress through heart rate variability (HRV), which reflects the variation in time between heartbeats rather than the heart rate itself [19][35]. - A healthy heart rate shows variability, while a low HRV indicates stress, but this does not differentiate between psychological and physiological stressors [30][47]. Group 3: Physiological vs. Psychological Stress - Various factors, such as caffeine intake, exercise, and emotional excitement, can lower HRV, leading to misleading stress readings from smartwatches [39][45]. - The article highlights that physiological stress can trigger the same responses as psychological stress, complicating the interpretation of HRV data [38][46]. Group 4: Limitations of Wearable Technology - The article points out that wearable devices often lack the capability to provide a nuanced understanding of stress, as they primarily focus on HRV without considering other factors [58][60]. - Clinical assessments of psychological stress involve a multi-dimensional evaluation, which smartwatches do not provide [57][75]. Group 5: User Misunderstanding and Marketing - There is a concern that marketing for stress-monitoring apps may mislead users into believing that these devices can accurately measure psychological stress [63][64]. - While these apps can provide some insights into overall physiological load, they should not be relied upon for precise psychological assessments [70][74].

Core Viewpoint - The accuracy of stress monitoring by smartwatches and apps is questioned, as many users report discrepancies between their perceived stress levels and the readings from these devices [4][12][55]. Group 1: User Experiences - Many users have shared experiences where their smartwatches inaccurately indicated high stress levels during relaxed situations or low stress during stressful times [6][11][14]. - The inconsistency in stress readings has led to skepticism about the reliability of these devices [4][12]. Group 2: Measurement Methodology - Smartwatches typically measure stress through heart rate variability (HRV), which reflects the variation in time between heartbeats rather than just heart rate [17][33]. - A healthy heart rate shows variability, while a low HRV indicates stress, but this can be influenced by both psychological and physiological factors [29][36]. Group 3: Physiological Influences - Factors such as caffeine intake, exercise, and alcohol consumption can also lower HRV, leading to misleading stress readings from smartwatches [37][40][44]. - Emotional states, such as excitement or anxiety, can similarly affect HRV, complicating the interpretation of stress levels [45][46]. Group 4: Research Findings - A study involving 781 students found that the stress levels reported by smartwatches did not align with the participants' self-reported stress, indicating a disconnect between device readings and actual psychological states [49][54]. - The study highlights that wearable devices measure a broad physiological load rather than specific psychological stress [57]. Group 5: Industry Insights - There is a lack of clarity in how manufacturers communicate the capabilities of their devices, often leading to misconceptions about their ability to measure psychological stress accurately [61][64]. - While some developers provide accurate explanations of HRV, others may mislead users into believing their devices can precisely monitor psychological stress [62][66]. Group 6: Practical Implications - Understanding the limitations of HRV measurements can help users appreciate the broader context of their physiological state rather than relying solely on these readings for psychological insights [70][71]. - Smartwatches and apps can still serve a purpose in providing general health insights, but they should not be solely relied upon for accurate psychological stress assessment [68][73].