Assertion: stretch | /r/HasProperty | effective
Facets:
Source sentences:
text: This is an excerpt from one of my school text books, a weighty and authoritative tome, a bible of therapeutic exercise (granted, out of date now, but this is the text I learned from): Several authors have suggested that a period of 20 minutes or longer is necessary for a stretch to be effective and increase range of motion when a low-intensity prolonged mechanical stretch is used.