How did a tall drink of water knock down a tree trunk?
Zimmerman is 110 pounds heavier...
Trayvon Martin was 6'3" and weighed 140 pounds at the time of his death.
George Zimmerman at the time of the incident, was 5 ft 9 in (1.75 m) tall,[6][31] and weighed approximately 250 lb
http://en.wikipedia.org/wiki/Shooting_of_Trayvon_Martin