Table 3.

Main sources of classes and their definitions in Exercise Medicine Ontology.

	Source	Usage
Ontology	Basic Formal Ontology	Top-level ontology
	Relation Ontology	Reuse relation
	Disease Ontology	Reuse disease
	Human Developmental Stages	Reuse human stage related concepts
	Ontology of Physical Exercises	As a reference
	OPTImAL	As a reference
	Physical Activity Ontology	As a reference
Guideline	WHO guidelines on physical activity and sedentary behaviour	Extract some concepts and relations between them
	National Fitness Guideline (China)
	Physical Activity Guidelines for Americans
	Physical Activity and Exercise Guidelines for All Australians
	UK Chief Medical Officers’ Physical Activity Guidelines
	The National Guidelines on Physical Activity for Ireland
	Physical Activity Standards for Health Promotion 2013 (Japan)
Database	Medical Subject Headings	Extract some concepts and their definitions, as well as the relations between them
	National Cancer Institute Thesaurus
	PubMed
	Systematized Nomenclature of Medicine–Clinical Terms
	Unified Medical Language System
	Wikipedia