Table 2.

Physical activity and exercise-related ontologies.

	EXMO	OPE	OPTImAL	PACO
Axiom	9732	3863	3170	1153
Class count	434	634	142	224
Classes with no definition	115	634	142	217
Usage	reference	reference	application	reference
Synonym	√	×	×	×
Top-level ontology	BFO	—	—	—
Health status	√	×	×	×
Physical activity	√	√	×	√
Exercise equipment	√	√	×	√