This study examined whether compliance with the 24-h MG combination was associated with HRQoL in three East Asian (Japanese, Chinese, and South Korean) children aged 7–12 years. Our significant findings were consistent with those of previous studies, demonstrating that meeting all 24-h MGs was not only associated with better HRQoL in children from three East Asian countries [21, 22] but also significantly associated with the HRQoL subfactors of physical well-being, psychological well-being, and social support and peers. Our results suggest that meeting all recommendations, rather than meeting one, two, or more within the 24-h MG, would be most beneficial for children's HRQoL. Therefore, taking an integrated view of all movement behaviors throughout the day in order to improve HRQoL is essential. Furthermore, the low proportion of children meeting all behavioral guidelines in this study (3%) underscores the need for specific, targeted interventions for PA, ST, and SD that focus on improving the rate of meeting each of these guidelines. This requires families, schools, and communities to work together to develop programs and environments that make it easier for children to enjoy a healthy SD, limit ST during play and leisure, and engage in a range of PAs, using a social-ecological model [40, 41].
Another notable finding was that physical well-being, a subfactor of HRQoL, was significantly associated with each of the seven movement behaviors outlined in the 24-h MG. Although meeting all 24-h MGs resulted in the highest percentage increase in physical well-being, this is an important finding that suggests that meeting PA, SD, and ST guidelines as individual movement behaviors may also be beneficial in improving HRQoL. Previous research has also highlighted the benefits of PA, with children who maintain an active lifestyle reportedly enjoying better physical well-being than those who do not [42, 43]. Moreover, the lack of adequate SD can affect the body's immune system [44], and increased use of TV, video, and mobile devices can lead to problems with physical well-being such as weight gain [17]. These results are consistent with previous studies revealing that PA, ST, and SD are movement behaviors that are strongly associated with physical well-being throughout the day [45]. In contrast, studies on Chinese children have found that ST and SD do not significantly impact physical fitness [46], while those that have examined the association between PA, ST, and HRQoL in children have generally found consistent links between the variables. In particular, this study found an average obesity rate of 14.7% in children from three East Asian countries, but according to a report by United Nations Children’s Fund (UNICEF), the obesity rate among school-aged children in East Asia increased from 10.4–27.5% in 2000, the steepest increase in the world [47]. As obesity is an important health determinant of physical well-being, the application of obesity prevention programs is also necessary to improve HRQoL[48]. However, because studies examining the association between SD and HRQoL are few and report mixed results [49], and because individual or combined behaviors are not equally important in predicting physical well-being within the constraints of a 24-hour day, further research is needed to gain deeper insights into their potential impact on primary school populations.
Next, psychological well-being, another subfactor of HRQoL, was significantly associated with sleep and a combination of two or more 24-h MGs. Among these, meeting SD recommendations is an important behavior that influences more than one recommendation, supporting previous research based on the 24-h MG framework linking it to psychological well-being [50, 51]. Adequate sleep during childhood is crucial because children who are sleep-deprived may feel tired during their daily routines, which can affect their ability to perform physical tasks such as engaging in physical fitness [52]. This finding is also consistent with previous research revealing that meeting two or more recommendations is associated with psychological well-being. For example, more PA and better SD in a 24-hour day are beneficial for psychological well-being, while higher SD is detrimental for psychological well-being [51]. However, the study reveals that the proportion of participants meeting each recommendation varies widely: 51.9% of children from three East Asian countries in this study met SD recommendations, while 41.3% met the ST recommendations and only 5.7% met the PA recommendations. According to the 2023 World Happiness Report, Japan ranks 47th in happiness, South Korea 57th, and China 72nd [53]. To improve the psychological well-being of children from three East Asian countries, efforts should be made to not only limit play and ST during leisure time but also develop environments where children can engage in a variety of PAs, among other components of the 24-h MG.
Finally, among the HRQoL subfactors, social support and peers were significantly associated with a combination of PA and two or more 24-h MGs. To date, social support and peers have primarily been studied in relation to individual movement behavior, with positive relationships having been observed between PA [54] and SD [55] and negative relationships with ST [56]. However, in our study, not only PAs during movement behaviors, but also PA + ST, PA + SD, and all combinations were significantly associated, which may play an important role in improving HRQoL in children from three East Asian countries. In particular, our findings confirm the high participation rates of children in Japan and South Korea, where the participation rate in sport is around 30%. Organized sports activities are reported to be more beneficial for children than unstructured activities, and this may have influenced the results by providing more positive peer interactions [57, 58]. In general, children's health behaviors are strongly supported by their parents in the early primary school years, with peer support increasing as children progress through school due to the need to gain acceptance and respect from peers [59] The association between peer support and sleep problems was stronger in younger than in older children [60]. Moreover, because peer victimization and bullying do exist and can affect health behaviors, it is crucial to identify and improve peer relationships through interactions with peers, teachers, and parents.
This study has several limitations. First, its cross-sectional design precludes causal inferences about the relationship between 24-h MGs and HRQoL. Second, because it is based on a cross-sectional sample of children in primary school (aged 7–12 years), caution should be exercised in generalizing the findings to other age groups, such as those in early childhood or adolescence. Third, although this study recruited samples from three countries in East Asia, they were from large cities in each country, such as Seoul, Sendai, and Shenyang, excluding children living in rural areas; thus, they are not representative of the population in each country. Economically disadvantaged children may have poorer physical health, which may directly affect their HRQoL [61] and further research is recommended for this segment of children based upon the health equity model [62]. Finally, it is noteworthy that the HRQoL data used in the analyses for this study were obtained from parental reports and therefore provide a single perspective and may not fully capture a child's perceived health status.