Job vs leisure: Rethinking physical activity as a precision strategy for mental and cognitive aging in China

Abstract

Mental and cognitive decline represent major challenges in aging populations. Physical activity is widely promoted as a key strategy for healthy aging. However, its effects are not uniform and depend on purpose and context. Job-related physical activity (JPA), often characterized by high demands and limited autonomy, may induce chronic stress, insufficient recovery, and adverse neurocognitive outcomes. In contrast, leisure physical activity (EPA) is typically self-directed and socially engaging, supporting improved mood, neural plasticity, and cognitive function. In this review, we reconceptualize physical activity by distinguishing JPA from EPA and propose a precision-oriented framework for mental and cognitive aging. We first examine their differences in psychological meaning, autonomy, and recovery patterns, then discuss the underlying biological, psychological, and recovery-related mechanisms, as well as socioeconomic and contextual influences. Finally, we outline implications for public health and clinical practice, emphasizing a shift from volume-based metrics toward context-sensitive strategies to promote brain health in aging populations.

Key Words: Job-related physical activity; Leisure physical activity; Depression; Cognitive aging; Healthy aging

Core Tip: Not all physical activity is beneficial-its purpose and context determine its impact on mental and cognitive health. This review highlights the fundamental distinction between job-related and leisure physical activity, showing that occupational activity may increase stress and cognitive risk, whereas leisure activity supports emotional well-being and brain function. By integrating biological, psychological, and socioeconomic perspectives, this article proposes a precision-oriented framework that moves beyond simple activity metrics and provides new directions for public health and clinical strategies in aging populations.

INTRODUCTION

China has a fast-growing aging population. A significant proportion of older adults experience mental health challenges, including depressive symptoms and cognitive decline[1-4]. Depressive symptoms and cognitive decline are prevalent among older adults, leading to a decrease in quality of life and increased healthcare demands[5,6]. China’s national reports show that the number of people aged 60 years and above continues to rise every year. This creates a strong need to find simple and effective ways to protect brain health in daily life[7,8].

Physical activity is often seen as a good habit for mental and cognitive health[9]. Many studies show that being active can improve moods and support brain function[10-13]. However, most studies treat physical activity as a single, undifferentiated behavior, which overlooks existing research on the “physical activity paradox”[14-17]. While some studies suggest that all physical activity is beneficial, others highlight the complexities and nuances in how different types of physical activity affect health outcomes. In real life, some physical activity is required for work job-related physical activity (JPA), while other activity is done for entertainment or exercise leisure physical activity (EPA)[18]. These two types may have significantly different impacts on mental and cognitive health. This oversimplification may lead to misleading conclusions and ineffective health recommendations, particularly in aging populations where the context of physical activity plays a critical role.

In light of these limitations, a more refined and context-sensitive framework is needed to understand how physical activity influences mental and cognitive aging. This review reconceptualizes physical activity by distinguishing between job-related and leisure-based movement, and proposes a precision-oriented perspective that integrates purpose, autonomy, and recovery into the evaluation of activity-related health effects. Specifically, this article first redefines physical activity through the lens of “job vs leisure”, then examines the biological, psychological, and recovery-related mechanisms underlying their divergent impacts. It further situates these differences within broader socioeconomic and contextual conditions, and finally discusses the translational implications for public health strategies and clinical practice in the context of aging populations in China.

RECONCEPTUALIZING PHYSICAL ACTIVITY: JOB VS LEISURE

A growing body of research suggests that not all physical activity leads to uniformly beneficial health outcomes. Rather than being a homogeneous behavior, physical activity varies substantially in its purpose, context, and psychological meaning[19]. In particular, an important distinction has emerged between JPA and EPA[18]. Evidence from recent studies indicates that vigorous JPA is often characterized by high physical demands, time pressure, and limited autonomy. Such conditions can lead to accumulated fatigue, elevated stress levels, and insufficient recovery, all of which are associated with an increased risk of depressive symptoms and accelerated cognitive decline in older adults[20-22]. For individuals engaged in physically demanding occupations, the inability to adequately recover after prolonged exertion may result in chronic physiological and psychological strain, ultimately undermining both mental well-being and cognitive function.

In contrast, EPA demonstrates a markedly different profile. EPA is typically self-initiated, flexible in intensity, and often embedded within enjoyable or socially engaging contexts[23,24]. Activities such as walking, tai chi, or recreational exercise are associated with positive emotional experiences, enhanced motivation, and greater perceived control. These factors contribute not only to improved mood but also to better cognitive functioning, as engagement in voluntary and enjoyable activities has been linked to enhanced neural plasticity and psychological resilience. Importantly, EPA often incorporates social interaction, which further supports emotional well-being and cognitive health in aging populations[25]. To facilitate a clearer comparison, the key differences between job-related and EPA are summarized in Table 1.

Table 1 Comparison of job-related and leisure physical activity across key dimensions.

Dimension	Job-related physical activity	Leisure physical activity
Purpose	Work-related obligation	Voluntary activity
Autonomy	Low	High
Intensity	Often high and prolonged	Usually moderate and flexible
Recovery	Limited recovery time	Adequate recovery possible
Psychological experience	Stress, fatigue	Enjoyment, motivation
Social interaction	Limited or absent	Often present
Cognitive impact	Potential risk	Protective effect

These contrasting effects challenge the conventional assumption that “more physical activity is always better”. Instead, they highlight the importance of considering the purpose and context of movement. Physical activity should therefore be reconceptualized not merely as a function of volume or intensity, but as a context-dependent behavior shaped by autonomy, meaning, and recovery opportunities. This perspective aligns with the emerging notion of the “physical activity paradox”, which emphasizes that occupational and leisure activities may exert fundamentally different physiological and psychological effects despite similar energy expenditures. Recognizing this distinction is critical for advancing a more nuanced understanding of how physical activity influences mental and cognitive health.

From this perspective, the divergent health outcomes associated with JPA and EPA cannot be explained solely by differences in energy expenditure. Rather, they reflect complex interactions between biological responses, psychological experiences, and recovery processes. To further elucidate these differences, it is necessary to examine the underlying mechanisms that link the purpose of physical activity to mental and cognitive outcomes. These mechanisms can be understood across biological, psychological, and recovery-related domains. The conceptual framework summarizing these pathways is presented in Figure 1.

Figure 1 Conceptual framework linking job-related and leisure physical activity to mental and cognitive aging. BDNF: Brain-derived neurotrophic factor; JPA: Job-related physical activity; EPA: Leisure physical activity.

MECHANISTIC INTERPRETATION: BEYOND “EXERCISE VOLUME”

Regular physical activity can help brain health, but why it helps depends on how the activity is done. Moderate EPA can improve the brain through biological changes. It can increase brain-derived neurotrophic factor (BDNF), which supports the growth and protection of brain cells, especially in the hippocampus, a key region for memory[26-31]. It can also improve blood flow and help the brain process information more smoothly[32-34]. These effects may slow age-related cognitive decline in older adults[35]. However, measuring BDNF in large-scale epidemiological studies presents a significant methodological challenge[36]. Standardized protocols for biomarker collection across different work environments are essential for ensuring accurate measurements and for drawing reliable conclusions about the effects of different types of physical activity on brain health. In contrast, vigorous JPA often means long hours of hard work with high stress. While prior studies suggest that such strain may raise cortisol levels over time through the stress response system, leading to potential brain cell damage and increased inflammation, these biological mechanisms are derived from theoretical interpretations and require further empirical validation[22]. These changes can speed up both physical and cognitive aging. However, measuring cortisol levels consistently in large populations is challenging due to variations in cortisol secretion patterns, the timing of collection, and individual differences. Standardized protocols for cortisol collection across diverse populations and work environments are needed to enhance the precision of research in this area.

Psychological factors also create differences between work activity and leisure activity. When older adults choose their own exercise, they often feel more control, more motivation, and more enjoyment[37]. These positive experiences can improve mood and support brain reward systems, helping reduce depression risk[38]. Many leisure activities also include social interaction, which can further improve emotional well-being[39,40]. Job-related activity, however, is usually done because people must work. It may bring less emotional reward and more stress, especially when people have limited control over their tasks or work conditions. This lack of choice can reduce motivation and increase mental strain[21].

Recovery is another important part of cognitive health. Heavy physical jobs may cause strong tiredness every day[41,42]. Older adults may not recover quickly after work, which can make thinking more difficult over time[43]. Long-term lack of recovery can harm both mood and memory. Leisure exercise is often easier to control. People can stop when tired, take breaks, and keep a more relaxed pace. These activities can help balance emotions and support social thinking skills, which may help protect the brain during aging[40].

SOCIOECONOMIC AND CONTEXTUAL FACTORS

Beyond individual-level mechanisms, the relationship between physical activity and mental and cognitive health is deeply embedded within broader socioeconomic and contextual conditions[44-46]. The distribution, experience, and health impact of physical activity are not random but are structured by social inequalities, occupational demands, and access to resources[47]. As such, understanding the differential effects of job-related and EPA requires a contextualized perspective that considers how socioeconomic status (SES) shapes both exposure to physical activity types and the capacity for recovery, autonomy, and health maintenance.

In addition, people who work in heavy labor jobs, typically linked with lower SES, may not have enough time or resources to recover after work[48]. The long-term physical strain combined with the systemic stressors of low SES, such as limited healthcare access and poor living conditions, may exacerbate cognitive decline and mood disorders. This highlights the importance of disentangling the physical strain of work from the broader socioeconomic stressors when designing precision movement strategies for older adults.

EPA tells a different story. Moderate exercise done by choice, such as walking with friends or doing tai chi, can help improve emotional well-being, particularly for individuals in higher SES groups who have greater access to leisure activities and healthcare. However, those in lower SES groups may face barriers to engaging in such activities, further complicating the potential cognitive and emotional benefits. These enjoyable activities support better brain function and help people stay socially connected[40]. Positive feelings gained during leisure activities may help protect brain health, even when individuals are getting older[33].

Taken together, these patterns indicate that the health effects of physical activity cannot be fully understood without considering the broader social and environmental context in which movement occurs. The apparent benefits or harms of physical activity are shaped not only by its intensity or duration but also by the degree of autonomy, resource availability, and recovery opportunities associated with it. This perspective underscores the need to move beyond a universal “more is better” approach toward a context-sensitive, equity-oriented framework. Integrating socioeconomic factors into the conceptualization of physical activity is therefore essential for developing effective precision strategies that address both behavioral and structural determinants of mental and cognitive aging.

TRANSLATIONAL IMPLICATIONS: A PRECISION MOVEMENT STRATEGY

Physical activity is helpful only when it matches people’s needs and abilities[49-52]. These findings can guide new strategies for public health and clinical care. In China, healthy aging is a national goal. Adding moderate leisure exercise into the Healthy China 2030 actions may help many older adults stay healthier for longer years[53-56]. Many older adults in rural areas have fewer resources and less access to social sports programs. More low-cost community exercise programs, such as square dancing and group walking, can support both mental and cognitive health in these regions[57,58].

People who work in jobs with high physical demand often face higher risks for depression and cognitive decline. These workers may benefit from early screening for mental and cognitive problems using tools like the Center for Epidemiologic Studies Depression for mood and the Mini-Mental State Examination for cognitive function[59,60]. A “precision” algorithm should integrate these screening tools with an evaluation of the individual’s occupational load and leisure capacity. For instance, clinicians could weigh the patient’s daily physical activity demands with their leisure time availability to prescribe an optimal exercise regimen that balances recovery needs and physical health outcomes.

Clinical practice can also use these findings. Exercise counseling should focus on purpose, personal choice, intensity, and incorporate standardized tools such as Patient Health Questionnaire-9 and the Montreal Cognitive Assessment to assess mental health and cognitive function. When prescribing exercise, clinicians should consider a patient's occupational load and leisure capacity. For example, individuals with high occupational physical demands may benefit from moderate leisure activities (e.g., tai chi or walking) outside work hours to promote recovery, while those with low occupational physical demands may engage in more intense activities tailored to their fitness level.

METHODOLOGICAL AND FUTURE RESEARCH DIRECTIONS

Future studies can test these findings with stronger methods. Longitudinal studies can help show how changes in physical activity over time affect mental and cognitive health within the same people as they age[61]. This kind of research can help answer questions about cause and effect. Using wearable devices may provide more accurate data about both the amount and purpose of physical activity in daily life. However, in the elderly Chinese population, the use of digital phenotyping may face specific challenges, such as low technological literacy and data privacy concerns, which can act as barriers to implementing “precision” strategies. These issues need to be addressed in future research, particularly by providing technological training for older adults and ensuring robust privacy protections for sensitive data. Digital tools, such as smartphone-based tracking, can also measure mood and stress in real time to better understand how activities influence mental health[62]. However, challenges related to technological literacy and data privacy among the elderly Chinese population may hinder the effective use of these tools. Future research should explore strategies to improve technology adoption in this demographic and ensure the ethical use of data through secure and transparent privacy protocols.

Biomarkers and brain imaging may help explain how different types of activity change the brain. Measuring BDNF and cortisol levels can show changes in brain plasticity and stress. Imaging tools, such as magnetic resonance imaging and positron emission tomography, can show which brain regions benefit from leisure movement and which regions are harmed by long-term heavy labor[63]. These methods can help connect physical behavior with biological changes in aging.

Health effects may not be the same for everyone. Future work can compare groups based on job type, gender, sleep patterns, and economic conditions to understand who is most at risk and who may benefit most from tailored activity plans. Clinical trials can also test whether adding enjoyable social exercise after work can reduce the negative effects of job-related activity on the brain and mood[43]. These intervention studies can help find the best ways to protect both mental and cognitive health in older adults who work in physically demanding jobs.

CONCLUSION

This review highlights that physical activity should not be understood as a uniform behavior, but as a context-dependent and purpose-driven process with distinct implications for mental and cognitive aging. The distinction between job-related and EPA challenges the conventional assumption that greater activity volume necessarily leads to better health outcomes. Instead, the findings presented here emphasize that autonomy, psychological meaning, and recovery opportunities are critical determinants of whether physical activity confers benefits or risks.

By integrating biological, psychological, and recovery-related mechanisms with broader socioeconomic and contextual factors, this review advances a more comprehensive framework for understanding how different forms of movement influence brain health in aging populations. In particular, it underscores that the health effects of physical activity are shaped not only by individual behavior but also by structural conditions that determine access to resources, time, and supportive environments.

These insights call for a shift from a generalized “more is better” paradigm toward a precision-oriented approach to physical activity. Public health strategies and clinical interventions should move beyond simple metrics such as total activity volume and instead incorporate purpose, context, and individual capacity when designing movement recommendations. Promoting accessible, enjoyable, and self-directed forms of leisure activity, while mitigating the risks associated with high occupational physical demands, may represent a more effective pathway to support mental well-being and cognitive health in aging societies, particularly in rapidly aging contexts such as China.