Comparison and Empirical Study of the Application of Compositional Isotemporal Substitution Model and Non-compositional Isotemporal Substitution Model in the Research Field of Health Effects of Physical Activity

Physical activity and health promotion is an important research field of public health and sports science. So far, some studies have explored the association between physical activity, sedentary behavior, sleep and various health outcomes separately.However, different behaviors in 24 hours are inherently co-dependent. In recent years, some scholars proposed an isotemporal alternative strategy to find the best time allocation method for achieving the maximum health benefits through the reallocation of time-use components. This study reviewed the development of current isotemporal substitution model in the research field of physical activity, and elaborated the theory of traditional isotemporal substitution model(i.e., non-compositional) and the compositional isotemporal substitution model as well as analyzed by examples. Based on the findings of this study, it is hope to provide new ideas and methods for sports science and public health researchers, and promote the application of isotemporal substitution model in the field of physical activity and health promotion.