put one's shoulder to the wheel vs start the ball rolling

put one's shoulder to the wheel

verb

  • Synonym of strive: To work hard, to complete an activity with one's complete effort and focus. 

start the ball rolling

verb

  • Synonym of get the ball rolling. 

How often have the words put one's shoulder to the wheel and start the ball rolling occurred in a corpus of books? (source: Google Ngram Viewer )