Sentence:  The simple mechanical strain of overweight , says New York 's Dr. Norman Jolliffe , can <WSD>overburden</WSD> and damage the heart `` for much the same reason that a Chevrolet engine in a Cadillac body would wear out sooner than if it were in a body for which it was built '' . 
Meaning of the word marked with <WSD> tags:  burden with too much work or responsibility