I must recommend the essay in OED at the opening of the entry for the prefix “out-“!  it is delicious.  “Stretch” is a verb of Germanic and Norse ancestry.

• 07.094 that lay outstretched far to North
• 18.053 shining over the outstretched lands.

“out-, prefix.” OED Online. Oxford University Press, June 2015. Web. 29 July 2015.

“stretch, v.” OED Online. Oxford University Press, June 2015. Web. 29 July 2015.