In the just passed "Double Eleven" shopping festival, smartwatches became a popular item in the field of smart wearables with their continuously upgraded health monitoring functions. On many e-commerce platforms' smartwatch detail pages, stress testing functionality has become one of the main selling points. Under the heat, doubts followed. On some social platforms, roast such as "the watch shows excellent health status after staying up late to play", "the watch prompts pressure overload when taking a holiday at the seaside" are common. So, can these smartwatches, which cost hundreds or thousands of yuan, accurately monitor stress? What is the difference between standardized stress testing used by professional medical institutions and daily monitoring of smart watches? The reporter from Science and Technology Daily interviewed relevant experts on this matter. Smart Watch Monitoring: Multiple Factors Causing Deviation in Results How Does a Smart Watch Monitor Stress? Associate Professor Chang Shuzhi from the School of Education and Psychology at Tianjin Sport University introduced that the stress assessment function of most consumer grade smartwatches currently relies on heart rate variability (HRV) as a physiological indicator. HRV refers to the small fluctuations in the continuous heartbeat interval of the human body, and its numerical changes directly reflect the regulatory function of the human autonomic nervous system. This system includes the sympathetic nervous system and the parasympathetic nervous system, with the former acting like a throttle, dominating the excited state to cope with stress; The latter is like a brake, responsible for relaxing and restoring the state. ”Li Shuhua, deputy chief physician of the Department of Psychology at Tianjin Teda Hospital, said that when a person is in a high-pressure state, the sympathetic nervous system will be excited and the HRV value will decrease; When a person is in a relaxed state, the parasympathetic nervous system dominates and the HRV value increases. Chang Shuzhi said that smartwatches will first continuously collect users' heartbeat signals, capture small differences in heartbeat intervals, and then analyze these data through built-in algorithm models to indirectly evaluate the activity status of sympathetic and parasympathetic nervous systems, ultimately calculating the user's current physical stress level and presenting it in intuitive stress scores. Regarding why there is a discrepancy between user experience and the stress score given by the watch, Li Shuhua explained that in addition to psychological stress, there are various physiological factors that can cause significant fluctuations in HRV values. For example, after staying up late, the body may become numb and fatigued, but at this time the HRV value may be stable, causing the watch to misjudge the user's "good condition". For example, during a seaside vacation, if one has just engaged in activities such as swimming or consumed caffeinated beverages, the sympathetic nervous system will continue to be active, leading to a decrease in HRV, and the watch will issue an error message of "pressure overload". Another issue lies in the evaluation model. Chang Shuzhi analyzed that most of these products adopt a "one size fits all" universal model. If the user's HRV value is below a fixed threshold, the model directly gives a judgment of "high pressure". This model ignores individual differences such as age, physical fitness, and basic health status. Everyone's baseline level of HRV is inherently different, and using a unified standard for evaluation will inevitably lead to bias in the results. In addition, the sensors of the watch are also susceptible to external factors. Chang Shuzhi introduced that smart watches rely on photoelectric sensors to obtain HRV data, but external factors such as wrist movement, skin color, and ambient light may interfere with the sensor's signal capture, leading to deviations in HRV measurement results and ultimately affecting the accuracy of the final evaluation. Professional Medical Testing: Comprehensive "Measurement" with Two "Rulers" So, what is the more scientific and accurate stress testing method currently available? In stress testing conducted by professional medical institutions, single indicator judgment has long been eliminated, and multidimensional and comprehensive testing has gradually become mainstream. This test is supported by rigorous medical theories, combined with authoritative standards and standardized tools. In clinical practice, no single indicator can independently determine stress levels, and doctors and researchers usually combine multiple indicators for comprehensive evaluation. ”Li Shuhua said that the core basis of this multidimensional evaluation is the physiological laws of human stress response - when the body is under pressure or falls into fatigue, a series of changes occur in the autonomic nervous system, endocrine system, etc., which constitute the physiological basis of the evaluation. At present, the recognized physiological indicators related to stress in the medical community are mainly divided into the following four categories, which correspond to different dimensions of stress states and complement each other. The first type is autonomic nervous system indicators, represented by HRV, which can to some extent reflect short-term stress states. The second type is endocrine indicators, such as cortisol, adrenaline, etc., which are suitable for evaluating chronic or long-term stress. The third type is immune indicators, and long-term stress can lead to changes in immune function such as a decrease in immunoglobulin levels and an increase in inflammatory factors. The fourth category is neurotransmitter indicators, including serotonin, norepinephrine, dopamine, etc. Stress can affect their secretion levels. To ensure the standardization of testing, all tests targeting physiological indicators must strictly follow international and domestic standards, such as the World Health Organization's (WHO) health assessment standards and China's "Technical Specifications for Occupational Health Surveillance". These documents clearly define the physiological and psychological judgment thresholds for stress fatigue, providing a judgment scale for test results. In addition to physiological indicator testing, we will also use standardized psychological scales that have been tested for reliability and validity to compensate for the shortcomings of physiological indicator testing. ”Chang Shuzhi introduced that commonly used scales include the Perceived Stress Scale, which is used to assess an individual's subjective level of stress perception, and the Maslach Burnout Scale, which specifically measures the level of burnout in occupational populations. These scales have undergone extensive clinical validation and can reflect subjective feelings that physiological indicators cannot reflect. Stress Management Guide: Self awareness is the key. "Stress itself is not a disease, but being 'wrapped' in stress for a long time may drag down one's health. ”Chang Shuzhi introduced that there is a threshold for the human body's tolerance to stress, and short-term stress can be relieved through self-regulation. However, sustained high pressure can disrupt the physiological balance of the human body, leading to disorders in cortisol secretion rhythm and autonomic nervous system function, resulting in symptoms such as persistent insomnia, emotional irritability, and lack of concentration. In the long run, it can also increase the risk of anxiety disorders, hypertension, and other diseases. The premise of stress management is to scientifically evaluate one's own stress level, which can be achieved for ordinary people without relying on professional equipment. The core method is to develop the habit of observing one's own stress signals, "suggested Chang Shuzhi. The public can focus on the following three aspects. The first is physical sensation, whether there is frequent fatigue, stiff shoulders and neck, headache or gastrointestinal discomfort, and whether the quality of sleep has decreased, such as insomnia, frequent dreaming or early awakening. The second is the emotional state, whether it becomes irritable, low mood, lacks patience, or difficult to feel happy. The third is cognition and behavior, whether it is difficult to concentrate, memory decline, whether it becomes withdrawn in social interactions, or whether it relies on smoking, drinking, and overeating to relieve emotions. When multiple signals mentioned above persist for more than two weeks and affect daily life, it prompts us to actively adjust or seek professional help. ”Li Shuhua said that this self-awareness based assessment is the first and most crucial step in stress management. On the basis of self-awareness, one also needs to learn how to scientifically relieve stress. Li Shuhua suggests that relieving stress does not require complex means, and low-cost and easy to persist methods should be prioritized. For example, setting aside 20 minutes every day for light exercise such as brisk walking and stretching to promote endorphin secretion; You can also relieve current tension through deep breathing, meditation, and other methods. In addition, establishing emotional "outlets" is equally important. Li Shuhua suggests that one can actively confide in trusted people about their confusion and release their psychological burden; If you prefer solitude, you can also shift your focus by writing a diary, listening to soothing music, cultivating gardening and other hobbies, temporarily relieving your body and mind from a high-pressure state. The key is to find a way that suits oneself and persist in it for the long term, while avoiding pursuing immediate decompression effects. (New Society)