impediment vs leg up

impediment

noun
  • Baggage, especially that of an army; impedimenta. 

  • A disability, especially one affecting the hearing or speech. 

  • A hindrance; that which impedes or obstructs progress. 

leg up

noun
  • A boost, a sudden improvement; an advantage, an edge. 

  • Assistance, help given to get started or overcome a problem or obstacle. 

  • The act of assisting another's progress over a wall or other obstacle by forming a step for one of their feet with one's hands. 

How often have the words impediment and leg up occurred in a corpus of books? (source: Google Ngram Viewer )