An Etymological Dictionary of the German Language/Annotated/strecken
strecken, verb, ‘to stretch, extend,’ from Middle High German stręcken, Old High German stręcchen, weak verb, ‘to straighten, make tense, extend, stretch’; corresponds to Dutch strekken, Anglo-Saxon stręččęan, English to stretch. The corresponding adjective strack (compare also Old High German stracchên, ‘to be extended’), points to a Teutonic root strak (for srak, a variant of rak in recken?), which is perhaps connected with the root of Strang and strenge. It is doubtful whether the High German cognates are borrowed from Italian straccare, ‘to exhaust, fatigue.’