1. Larson JS. The conceptualization of health. Med Care Res Rev. 1999;56:123–36. https://doi.org/10.1177/107755879905600201
2. De Carvalho Yokota RT, Van Oyen H. Operationalization of concepts of health and disability. In: Jagger C, Crimmins E, Saito Y, De Carvalho Yokota R, Van Oyen H, Robine JM, editors. International handbook of health expectancies. International handbooks of population, vol. 9. Springer, Cham; 2020. https://doi.org/10.1007/978-3-030-37668-0_1
3. Chatterji S, Ustün BL, Sadana R, et al. The conceptual basis for measuring and reporting on health. Geneva: WHO; 2002.
4. Caspersen CJ, Powell KE, Christenson GM. Physical activity, exercise, and physical fitness: definitions and distinctions for health-related research. Public Health Rep. 1985;100(2):126–31.
5. Physical Activity Guidelines Advisory Committee Report [PAACR] (2008) https://health.gov/sites/default/files/2019-09/PAG_Advisory_Committee_Report.pdf