As a prominent feature of the activity patterns of modern urban populations, the acceleration of the life rhythm has a profound impact on the physical and mental health of the public and the orderly operation of cities. Defining and quantifying the life rhythm is a crucial starting point for exploring its multifaceted impacts on human life. It not only helps in deeply understanding the behavior patterns and living conditions of urban residents but also holds great significance for enhancing the happiness of urban residents, improving the scientific nature of urban planning and management, and promoting the sustainable development of cities. This article focused on first-tier, new first-tier, and second-tier cities in China. Based on the theories of time geography, behavioral geography, and social ecology, a conceptual model of the life rhythm was constructed from two dimensions: activity duration and activity intensity. We used the Weibo check-in data from 2019 to 2024 to extract the activity patterns of urban populations and quantify the indicators of the life rhythm. The entropy weight method was employed to synthesize the life rhythm index, revealing the distribution patterns of population activities and the life rhythm from the perspectives of different date types, geographical locations, urban hierarchies, and gender groups. Finally, the partial least squares regression method was adopted to explore the main influencing factors of the life rhythm. The results show that:
(1) Overall, the activities of modern urban populations exhibit a pattern characterized by work, leisure, and home activities as the dominant modes. On working days, it follows the typical traditional pattern of going to bed early and getting up early, with the "9-to-5" workday, and work is the main activity. On non-working days, people tend to go to bed and get up later, with leisure and home activities taking the leading position. However, phenomena such as the increase in working hours on holidays compared to rest days (+4.2%), the decrease in the intensity of dining activities (-9.9%), and the neglect of breakfast on non-working days reflect that with the continuous acceleration of the development pace of modern society, traditional activity patterns are undergoing significant changes. The boundaries between work and life are becoming increasingly blurred, and the activities of modern urban populations are becoming more complex and diverse.
(2) In terms of the time pattern, the overall life rhythm shows a decreasing trend from working days to rest days and then to holidays. From 2019 to 2024, the life rhythm fluctuated greatly. It first gradually slowed down and reached the bottom in 2020, then rebounded rapidly and peaked in 2022, and has continued to decline since then, forming an overall change trajectory of "V-shaped reversal - peak callback". This change pattern is mainly affected by the fluctuations in the check-in quantity and duration of dining, leisure, and home activities. For example, the outbreak of public health incidents affected people's travel, resulting in significant fluctuations in the check-in quantity of home-related activities.
(3) Geographically, economically developed regions such as the Beijing-Tianjin-Hebei region, the Yangtze River Delta, and the Pearl River Delta have formed a geographical pattern of "high core and low periphery" for the life rhythm. Meanwhile, the working hours and intensity in these regions are both among the highest, with an average working duration of 10 hours and 50 minutes. In terms of residents’ overall work-rest time, the east and north see earlier schedules while the west and south see later ones. From the perspective of different urban hierarchies, there is a significant positive correlation between the life rhythm and the comprehensive development level of cities (r = 0.59, p < 0.01). The working hours and intensity also show a decreasing pattern of first-tier cities > new first-tier cities > second-tier cities. After re-clustering cities into four types: highly efficient and enterprising mature types, steadily driven growth types, comprehensively catching-up potential types, and balanced development and livable types, it is found that the social competition and pressure derived from economic development are increasingly intensifying. However, the life rhythm is influenced by various factors, and work activities and the quality of life are not contradictory to each other. A balanced and harmonious state can be achieved through reasonable planning and guidance.
(4) From the dimension of gender differences, men's indicators such as the life rhythm, relative work hours, and relative work intensity are 17.7%, 4.5%, and 30.5% higher than those of women respectively. On the other hand, women have a higher degree of participation in family life, which reveals the profound influence of traditional gender concepts on career development and family division of labor.
(5) Through regression analysis of the life rhythm and relevant social and economic statistical data, it is found that the population density of permanent residents (regression coefficient β = 0.067), the proportion of the population in the tertiary industry (β = 0.056), the total population of permanent residents (β = 0.037), and the proportion of the working population (β = 0.037) are the main positive influencing factors. Housing prices (β = 0.016) and the proportion of migrant population (β = 0.004) have a relatively weak positive impact on the life rhythm. GDP (β = -0.018) and the proportion of the population in the primary industry (β = -0.011) have a certain degree of reverse impact on the life rhythm. Therefore, the formulation and optimization of relevant policies regarding population management and industrial structure are the main directions of efforts for maintaining the balance of the life rhythm, improving the living experience, and enhancing the happiness of residents.