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 article discusses the inaccuracies of stress measurement by smartwatches and apps, emphasizing that the heart rate variability (HRV) used to gauge stress does not solely reflect psychological pressure but also includes various physiological factors [19][32][52]. Group 1: Measurement Methodology - Smartwatches typically measure stress through heart rate variability (HRV), which indicates the variation in time between heartbeats [19][30]. - A healthy heart rate shows variability, while a consistent rhythm indicates lower HRV, suggesting higher stress levels [20][28]. - The autonomic nervous system, comprising the sympathetic (SNS) and parasympathetic (PNS) systems, regulates heart rate and can influence HRV based on various stimuli [22][25]. Group 2: Factors Affecting HRV - Both psychological and physiological stressors can lower HRV, including caffeine intake, smoking, intense exercise, and emotional excitement [34][35][42]. - The smartwatch cannot differentiate between types of stress, leading to potential misinterpretations of the user's actual stress state [44][52]. Group 3: Research Findings - A study involving 781 students found a significant mismatch between smartwatch-measured stress and self-reported stress levels, indicating that wearable device data may not accurately reflect user experiences [46][49]. - The research concluded that wearable device data and self-reported data might represent different concepts, highlighting the limitations of current stress measurement technologies [50][51]. Group 4: User Perception and Misunderstanding - Many users may misinterpret the capabilities of stress-monitoring apps, believing they can accurately assess psychological pressure when they primarily reflect physiological load [56][62]. - The article suggests that while these apps can provide some value, they should not be relied upon for precise psychological assessments [59][65].

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].