Strongest leader? I wonder how he would stack up against Gerald Ford.
Well, Andrew Jackson was probably the toughest fighter of any President.
Nah, he needed a gun for his duels. Teddy could smash him any day. Washington in his prime would also be near the top, though by the end of his presidency he was an aged man.
Even if Romney is likely bigger and stronger than Obama, Obama would certainly be more agile, and his comparative youth likely wins it for him. The best comparison might be a TF2 fight between the Scout and the Soldier.