It surprises me that nearly everyone put "to look good"...
You do realise that most women don't find massive guys attractive?? Of course, fake tan, fake tit bimbos do, but that's because they're fake. ie, contrast between AFL wives and NRL wives. If you like that, then ignore this post.
Ask any girl or look on any 'who's a hot guy' poll and you'll see that number one is invariably David Beckham or some other lithe but toned to death sub 80kg dude. Look at Calvin Klein ads or any italian designer model. Or any guy girls find attractive. Sorry, but as a general rule its the truth. Obviously, some girls do like big dudes. This is the overwhelming exception, not the rule.
I think we get addicted to getting big, and if you truly want to just be good looking you'd have stopped years ago and upped the cardio. I guess what I am saying is that we like to be strong and assertive with other males... its not just about getting girls. Just like most girls, (ask your g/f) dress to impress other girls - if they're into fashion (might be a eastern suburbs thing). This excludes sluts of course.