What does "peack condition" really mean?

What does it really mean when people use it to describe guys like Captain America and Batman, Robin, Nightwing

It should mean that they can lift the maximum amount a human being can lift, run as fast as the fastest human, jump as well as the best acrobats. It means they're at the peak physical condition a human being can be at. Simple as that. Now this being comics, we sometimes see these characters exceed these limits.

I dont think I really understand

@flashrobin: just means they are at maximum physical capabilities that are achievable by humans in their respective universe.

If someone else who isn't super powered can physically do it, they can as well.

Peak human = what a human being can do.

Look at Olympic athletes. Take the best person from each of those categories - running, lifting, acrobatics, etc. Then combine all of them, and you get characters like Batman.

true

and true again

No idea what peack condition is.