The coronavirus (COVID-19) outbreak that began in December 2019 has become a global threat (1). In order to control the infection rate, the governments of China (2), Italy (3), Spain (4) and other countries have adopted isolation policies. Isolation has been the main control strategy for unforeseen epidemic outbreaks (4). In the face of infectious diseases, the general population may not choose to seek medical help because of an inability to recognize symptoms of disease or be aware of the risk of infection (5, 6). This may increase the risk of infection in people who are susceptible to the disease. Previous studies on other infectious respiratory disease pandemics have shown that closing some public places and schools and requiring people to stay at home as much as possible can effectively reduce infection rates (7, 8). In the early stages of the COVID-19 pandemic, the Chinese government launched an unprecedented emergency plan that included closing unnecessary businesses, public transportation and schools as well as transforming students' face to face learning into online learning. At the same time, the public is advised to cancel all non-essential activities and outdoor activities and isolate themselves at home as much as possible to reduce the rapid spread of infection and disease. Initially, this quarantine policy was only enforced in the Wuhan region of China, where the COVID-19 epidemic was most severe. With the rapid spread of COVID-19 across the country, the vast majority of China has begun to implement this quarantine policy. Although this isolation strategy reduces the chance of human-to-human transmission of COVID-19, it increases physical inactivity and sedentary behavior (9–12), and increases the occurrence of adverse psychological conditions, such as insecurity and fear can cause anxiety and stress (13, 14), thoughts of death, feelings of helplessness and abandonment (12). People spend more screen time during isolation (4), and sleep problems and circadian rhythm disturbances increase (4, 15).

In fact, it is important to maintain a certain level of physical exercise during isolation. On the one hand, physical exercise can modulate immune responses in people, especially those who are sedentary and inactive (16, 17). Numerous cross-sectional and longitudinal studies have demonstrated that regular physical exercise has multiple anti-inflammatory effects that may prevent all-cause mortality (18). A mouse experiment showed that moderate endurance exercise (30 min/day) could protect mice from influenza death (19). Older adults may have improved influenza vaccination responses after 10 months of moderate-intensity endurance training (20). At the same time, regular physical exercise has a wide range of mental health benefits, ranging from promoting mental health by improving emotional state (21), to reducing anxiety levels and perceived stress (22, 23). In addition, physical exercise can improve people's sleep status through a variety of psychophysiological pathways (15). In contrast, isolation is known to negatively impact individual immunity, for example by elevating glucocorticoids such as cortisol (24) and suppressing T-cell action (25). And T cells are critical effector lymphocytes that protect vulnerable areas such as the upper airway and lungs (26). Therefore, it is necessary to increase physical exercise during the isolation period.

However, despite the government's advice through the public media to maintain a certain level of physical exercise during the isolation policy of the COVID-19 pandemic, such social distancing measures have greatly reduced opportunities for physical activity in the general population and the incidence of physical inactivity very high (27, 28). During the COVID-19 pandemic, the majority of Chinese stayed at home 20–24 h a day (84.7%) (13). Zhang et al. found that PA in children and adolescents was at very low levels during the COVID-19 epidemic (29). However, less-reported studies exist on factors that may hinder home physical activity during isolation policies. Understanding the characteristics and related factors of people who did not engage in home physical exercise during the isolation policy period may be more conducive to formulating future infectious disease quarantine home health guidelines and policies. Considering the potentially harmful effects of physical inactivity, this study hopes to explore the incidence and influencing factors of non-participation in home physical exercise among Chinese students during the implementation of the COVID-19 isolation policy. These data may contribute to the future development of targeted empirical evidence to strengthen public health policy and guidance on pandemic containment.

In order to achieve the research objectives, this study mainly refers to the Anderson health/disease behavior model (30), and designed the questionnaire for this study. The Anderson health/disease behavior model has three components, including external environment, main feature, and health/disease behavior. The external environment and main feature determine health/disease behavior, which in turn affects main feature. The main features include forward leaning factors, enabling factors and demand factors. As shown in Figure 1, the theoretical framework analyzed in this study consists of three parts: the first is the external environment, which mainly refers to the important environmental variables that affect students who do not participate in home physical exercise. The second is the main feature, including forward leaning factors, enabling factors, and demand factors. The third is health/illness behavior, that is, whether the students participate in home physical exercise behaviors or not. As this study was planned, most regions in China had adopted COVID-19 isolation policies. Therefore, the external environment is mainly the isolation policy environment adopted by the state and governments at all levels. This study hypothesizes that forward leaning factors, enabling factors, and demand factors will all have a significant impact on students non-participating in home physical exercise.

This study provides important, updated evidence on Chinese students' home physical exercise during the isolation policy. Overall, the incidence of non-participating in home physical exercise among students aged 10–20 in our study was 25.86%, which is lower than that found in other Chinese research. And students of different ages have different incidences of not participating in home physical exercise, with the highest proportion of 16-year-old students. A previous study of Chinese adolescents showed that during the COVID-19 pandemic, the prevalence of physically inactive students increased from 21.3 to 65.6% (28). The reason for this difference from our results may be their physical activity assessment tools (IPAQ–SF), which are different than those used in this research. Due to the cancellation of face-to-face physical education classes and the drastic reduction in outdoor activities during the COVID-19 epidemic, most questionnaires on physical activity levels are not suitable for home physical exercise surveys. In addition, our investigation of the home physical exercise behavior of students seems to be more focused on the actual situations of Chinese families during the COVID-19 isolation policy.

Previous studies have found that gender and age are significant factors affecting the physical activity of adolescents during the COVID-19 pandemic (40, 41). However, in this study, although age and gender were not significant factors affecting students without home physical exercise, the results showed that the higher the grade of the student, the greater the risk of non-participating in home physical exercise, which is similar to Kang et al. (41). The research group has conducted surveys on the relationships between exercise intentions, exercise habits and physical health beliefs and the physical activity of students in previous studies. The survey results show that these are significantly positively correlated with the frequency of physical activity of students (42, 43). In the current study also observed that those non-participating in home physical exercise had lower exercise intentions, worse exercise habits and lower levels of health beliefs.

In this study, we observed that the longer the use of electronic products, the higher the risk of a lack of family physical exercise behavior in middle school students. This is consistent with the conclusions of some previous studies (28, 43). Schmidt et al. reported that during the COVID-19 pandemic, adolescents' total amount of leisure screen time increased significantly, and physical activity decreased significantly. The increase in total leisure screen time increased the students' sedentary time, which may have had a negative impact on their physical and mental health, and this deteriorating health may have further reduced their physical activity levels (44). Our research also found that students with poorer self-rated health status had a higher risk of lacking family physical exercise. Self-rated health status is an indicator of health status that can be used indirectly as an individual (45). Vingilis et al. reported that adolescents with better self-rated health status were more physical exercise (46).

This study examines the Anderson health/disease behavior model for the first time to explore the impact of multiple main feature factors on the home physical exercise behavior of Chinese students during the COVID-19 quarantine policy. We found that forward-leaning factors, enabling factors, and demand factors all had a significant impact on students' home physical exercise behavior during the isolation policy period. The study found that students who had no family members physical exercise, no family exercise recommendations, no school exercise guidance, and no Health education classes were more likely to not participate in home physical exercise. At the same time, this study also found that the lack of physical exercise conditions in the home environment also significantly affected students' home physical exercise during the isolation policy. The outbreak of COVID-19 in China coincides with the “Spring Festival,” the most important traditional Chinese festival. During this festival, Chinese families have the habit of getting together. COVID-19 isolation policies have increased the gathering of family members, which has led to a reduction in home physical exercise space, which may also affect students' lack of home physical exercise (47).

This study confirmed factors that may potentially affect students non-participating in home physical exercise during this isolation policy. Forward leaning factor(grade and belief in physical health), enabling factor (family members physical exercise, family exercise recommendations, home exercise conditions, school exercise guidance and health education classes), demand factor (exercise intentions, exercise habits, self-rated health status and electronic product use) and students' home physical exercise behavior were significantly associated. Based on the results of this study, it is suggested that in future health education, it is very important to increase students,” interest in physical exercise, cultivate students,” physical exercise habits, and enhance students,” belief in physical fitness. This may help improve physical activity for students when faced with public health restrictions. At the same time, the future health isolation policy should consider the role of forward leaning factors, enabling factors, and demand factors in promoting students” physical exercise. It is recommended that families and schools be included in the student health education program during the isolation period, which will help students adopt a more active lifestyle in response to the physical and mental adjustment of the isolation policy.

The advantage of this study lies in the large sample size, including students of different genders, grades, and regions (rural, urban, and urban). First, the population of this study is very representative, and the results can be used to support future student quarantine health education strategies and health care strategies for inclusion in quarantine policies due to public health emergencies. This study aims to provide recommendations to help promote physical activity promotion for students in segregated policy settings. Second, the survey data for this study was conducted during the COVID-19 quarantine policy, which occurred during a global pandemic health threat. The results obtained in this unique social model may have certain reference value for the design and implementation of physical activity strategies for global student health isolation policies.

A variety of forward leaning factors, enabling factors and demand factors have affected the occurrence of students' non-participating in home physical exercise. Future health isolation policies should take into account these influencing factors to reduce the occurrence of students' non-participating in home physical exercise and to promote students' independent participation in physical exercise.

This study also has some research limitations. First, the use of an online survey method, which will miss the collection of data on respondents, who cannot use online questionnaires. Secondly, the dissemination of the questionnaire is carried out in a “snowball” method, which will inevitably lead to skewed distribution of some indicators of the sample, such as the uneven age distribution of the respondents, which may partially affect the stability of the research conclusions. Third, the survey time is relatively short, and the investigators use the recall method to report themselves, which will inevitably lead to memory bias. However, from the research results, it is possible to peek into the important influencing factors of students' family physical exercise behavior under the COVID-19 isolation policy environment, which is of reference value for future research.

The raw data supporting the conclusions of this article will be made available by the authors, without undue reservation.

The studies involving human participants were reviewed and approved by the Ethics Committee of the Sports College of Guizhou Normal University (No. 20200227). Written informed consent to participate in this study was provided by the participants' legal guardian/next of kin.

During the research process, LL had full access to all research data and also analyzed the data and wrote the manuscript. NS participated in the research design. JH, HY, XZ, FA, QO, QJ, and YW collected the data. JD participated in the revision of the paper. All authors have read and approved this version of the article.

The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.