This study conducted a systematic cross-sectional analysis with a nationally representative sample to delve into the correlation between physical activity levels and the incidence of chronic diseases among the middle-aged and elderly population in urban and rural China. We found that 45.8% of the participants met the recommended levels of physical activity according to the guidelines. This finding not only aligns with previous research conducted within China but also[19], unexpectedly, is slightly higher than that of the United States[18],albeit lower than Australia[12].This disparity might reflect the influence of differing national cultures, lifestyles, and public policies on citizens' health behaviors, underscoring the need to consider these factors when promoting physical activity and designing public health strategies.
The "Healthy China 2030" planning outline issued by the Chinese government indicates an anticipated increase in the proportion of people regularly engaging in physical exercise (at least three times a week, with each session lasting 30 minutes or more, and at a moderate or higher intensity) to 37% and above by 2022-2030[20].Our study defines individuals participating in moderate to high-intensity physical activity for more than 30 minutes daily and engaging in such activities for more than five days a week, as well as those participating in vigorous physical activity for more than 30 minutes daily for at least three days a week, as meeting the guidelines. This classification aligns with the requirements set forth in the "Healthy China 2030" planning outline. Our findings reveal positive progress towards achieving the government's physical activity targets, especially among the middle-aged and elderly populations. However, despite 45.8% of the middle-aged and elderly reaching the recommended activity levels, over half of the population fails to meet these standards, highlighting the urgency to further increase participation rates, particularly in the context of promoting healthy aging[21][22].
“The 2020 National Fitness Activity Survey Report” released by the National Fitness Monitoring Center in 2022 shows a decreasing trend in the proportion of people engaging in physical exercise at least once a week with age. Our study similarly finds that the proportion of individuals participating in physical activity and meeting the guidelines decreases with age, a trend not only prevalent among adults over the age of seven but also within the middle-aged and elderly groups[23]. Furthermore, With higher educational attainment is associated with an increase in the proportion of individuals meeting the physical activity guidelines, and rural residents are more likely to meet these guidelines compared to their urban and semi-urban counterparts.Generally, individuals who rate their health as good or very good, non-smokers, and married individuals have a higher likelihood of meeting the guidelines than their counterparts.corroborating a universally observed trend[12][24]. Our study notes a higher proportion of females meeting the physical activity guidelines compared to males, differing from previous findings, possibly due to variations in urban-rural population ratios or overall better health status among women in our sample[12][24]. Interestingly, we found that individuals who consume alcohol are more likely to meet the physical activity guidelines than non-drinkers, possibly due to a generally better health status among the current drinking population, similar to the observed gender differences[25].
Given these insights, our study's results hold significant implications for designing and implementing targeted health promotion and disease prevention programs. For instance, policymakers and public health experts could use these findings to develop physical activity programs specifically designed for the middle-aged and elderly, taking into account factors such as education level, residential area, and gender. Moreover, our results support the recommendation to intensify health lifestyle promotion efforts, particularly in increasing physical activity levels. To achieve broader public health goals, future policies and interventions should not only focus on increasing the frequency and intensity of physical exercise but also on integrating physical activity into daily life, such as encouraging walking, cycling, and household chores. Providing safe, convenient public health facilities and environments to facilitate physical activity among the middle-aged and elderly will be key to enhancing participation rates.
Recent research on physical activity has primarily focused on the effects of guideline-compliant physical activity, varying intensities of physical activity on health outcomes, and chronic disease incidence rates, including the study of optimal timing for physical activity and its health-promoting effects[12][26]. Our study observes a less frequent distinction between individuals not engaging in physical activity and those not fully meeting the guideline recommendations in their impact on chronic disease incidence rates, with previous research often grouping these individuals together as failing to meet the guidelines. Our study differentiates these groups to achieve our research objectives and conducts a combined analysis in the latter part for a more comprehensive comparison with previous studies.
We categorized our sample into three groups: level 1 (no physical activity), level 2 (participating in physical activity but not meeting requirements), and level 3 (meeting the physical activity guidelines). The first part of our analysis explored the disease incidence rates among these groups and adjusted odds ratios (ORs) for confounding variables, finding that for individuals in levels 1 and 2, ORs for 8 chronic diseases were below 1, suggesting that engaging in physical activity, even if not meeting the guidelines, can still promote health. Individuals in level 3 (meeting the guidelines) showed lower incidence rates for 11 chronic diseases compared to those not engaging in any physical activity. Thus, while partial adherence to physical activity guidelines indeed offers significant health benefits, fully meeting the guidelines yields greater benefits[28][29][35]. Consequently, governments and organizations should encourage the public to engage in more physical activity to meet the guidelines. To better compare with previous studies, we combined the groups not engaging in physical activity (level 1) and those participating but not meeting the guidelines (level 2). The adjusted regression equation results, controlling for confounding factors, indicated that for the combined group (level 1+level 2), compared to those meeting the guidelines (level 3), ORs for 10 diseases were below 1, further justifying the rationale for encouraging more physical activity to meet the guidelines rather than merely participating[5][6][8][9][28][29][30][35].
Previous research has associated all 15 chronic diseases studied with insufficient physical activity[5][30][33][34][35][36], but our study found that the incidence rates for liver diseases, stomach diseases, and arthritis or rheumatism did not decrease as expected in the group meeting the physical activity guidelines, after adjusting for covariates. This discrepancy with previous studies could be due to our amalgamation of similar chronic diseases, such as arthritis and rheumatism, potentially affecting our results, as prior research has shown protective effects of physical activity on arthritis. Additionally, while some physical activity studies indicate that not all chronic diseases are related to physical activity, further research is needed to confirm these findings[35].
Despite this study providing valuable insights into the association between physical activity and chronic disease incidence rates among the middle-aged and elderly in China through a nationally representative sample, there are several limitations to note. Firstly, as our results rely on self-reported questionnaire data rather than objective measurement tools (such as accelerometers or pedometers), they may be subject to recall bias and social desirability bias[31]. This could lead to an overestimation or underestimation of physical activity levels. Future research should consider using these objective tools to provide more accurate quantitative data on physical activity[37][38]. However, in the field of public health, standardized questionnaires are often the preferred method for measuring physical activity due to their low cost and established reliability and validity[32].Secondly, although our questionnaire was designed with reference to internationally standardized questionnaires and aimed to achieve reliability and validity, the division of physical activity levels may differ due to the lack of precise timing data, which could affect the proportions of activity levels reported[17][38]. Lastly, due to the cross-sectional study design employed, we cannot determine the causal relationship between physical activity and chronic diseases. While we observed a significant association between the two, this design limits our interpretation of whether physical activity directly leads to a reduced risk of chronic diseases. Thus, future longitudinal or intervention studies are needed to further explore this relationship.