barren vs on a treadmill

barren

adj
  • Unable to bear children; sterile. 

  • Of poor fertility, infertile; not producing vegetation. 

  • Mentally dull; stupid. 

  • Bleak. 

  • Unproductive; fruitless; unprofitable; empty. 

noun
  • An area of low fertility and habitation, a desolate place. 

on a treadmill

How often have the words barren and on a treadmill occurred in a corpus of books? (source: Google Ngram Viewer )