system
Given the following post, respond as if you're commenting on Reddit:
human
[Marvel/DC] As buff as everybody is, how are they able to fight crime? Shouldn't they constantly be sore/weak from the gym?

The types of physiques superheroes rock take serious, dedicated bodybuilding routines. You have to have hardcore workout sessions most days of the week in order to simply maintain those muscles. 

Some characters like Batman slap on all the plates they can fit on a barbell in order to workout. How does Batman have the ability to work out with world record lift numbers and still have the ability to respond in case Bane attacks later that night? I doubt any MMA fighters do serious lifting on their fight days. They want to be at their peak and stay fresh for the fight.
gpt
Batman spent years training before he even started fighting crime so he was already pretty dam buff. After a certain point you don't have to work out as hard and just make sure you are actually exercising (which Batman does) to maintain that physique. Also, keep in mind that just because you worked out a muscle a day before doesn't mean you'll wake up sore. That usually happens when you first start working out.

If they are in pain because of their workouts they can still soldier on as most superheroes are shown to have a pretty decent pain tolerance. I.e. Batman getting stabbed/shot, Spider-Man being buried alive, Green Lantern having his arm broken and so on.