Assertion: small dark muscle fiber | /r/HasProperty | resistant
Facets:
value: very
type: DEGREE
value: to fatigue
type: PURPOSE
Source sentences:
text: Motor Unit Slow (S) motor units stimulate small muscle fibers, which contract very slowly and provide small amounts of energy but are very resistant to fatigue, so they are used to sustain muscular contraction, such as keeping the body upright.