Well... there have been lots off assholes that have put on a uniform that doesn't make them a hero. John Lee Mohammed for example. Timothy McVeigh is another that has worn that uniform. Are they heroes?
Your body stays proportionate to itself so if you're not working your legs your upper body will only be so big as well. Yeah, working the upper body will definetly get you cut but you seriously limit building muscle mass by ignoring you legs.