What is the Deal with Superman's Muscles?

Did DC Comics miss out on making a much more interesting superhero?
In the interest of not being very serious, I ponder the physique of the man who is considered by many to be the greatest of superheroes.
There are a lot of things one can ponder regarding Superman. Superdickery.com asks the important question “Why is Superman such a dick?” (excellent examples of superdickery here, here and here), and David Shultz wonders why Superman’s powers are growing so fast (maybe even faster than God’s are shrinking, even though Shultz’ diagram at the end doesn’t take God’s shrinking powers into account). I have a different question though.

I wasn’t really a fan of superhero comic books when I was a kid, but I did read some of them. I never really liked Superman though. He was just too strong, too fast, too good, too invulnerable; just too perfect. It felt boring.

Then I started thinking; every single time you see drawings of Superman, especially in his later incarnations, he is really bulging with muscles. He is ripped. He is the Man of Steel. He has muscles coming out the wazoo (probably). But the question is, why?

From what I know about the man of oh-so-little fashion sense, his strength comes from utilizing the energy from our yellow sun. When he is subjected to its life-giving rays he becomes super-fast, super-strong and super-able-to-disguise-himself-with-just-a-pair-of-glasses.

Because he has super strength, many feel that it is natural that he should have gigantic muscles. But is that really so? If it is anything resembling human muscles, they could never do all the things that Superman does without tearing asunder. It would just be too much strain, no matter how massive they are. So it feels like he would be using some kind of mystical (solar-powered) energy to perform his feats, not his muscles.

Besides that, again if he functions in any way resembling humans, muscle mass is usually gained through exercise, but I’d say that Superman almost never works out. Nothing he does seems taxing to him!

Just imagine what a basic set of cardio exercises would have to be for Superman. The guy can fly from on side of the world to the other in moments, arriving without being out of breath or sweaty, with no visible signs of having done any physical activity at all. Not to mention that he once flew so fast around earth that time went backwards (for no apparent reason). That has to be really, really fast, and he still didn’t look like he had gotten even a basic workout from it.

And we shouldn’t even talk about things like weightlifting. The man can lift just about anything and only shows any strain from it when it’s needed for dramatic effect. He could never pump up any good muscles without finding some steady point to stand on and weight lift the entire freaking planet.

Now I realize that everything I’ve said is contingent on him working in a human-like fashion. Maybe they explain this at some point and say that his muscles are formed by the yellow rays from our sun, and that’s why they are so huge; saying that he doesn’t have to work out to have huge muscles.

But I say, so what? That might be a reasonable explanation (within the confines of the DC universe), but it isn’t much fun. At least not to me. I think that Superman would be an infinitely more interesting Superhero if he had all his powers, but was chubby and flabby from lack of proper exercise.