system
Given the following post, respond as if you're commenting on Reddit:
human
[Man of Steel] How physically strong are Kryptonians when they are in a Kryptonian environment?

So in the beginning of the movie we have a nice fight scene between Zod and Jor-El. How strong are these guys when they're on their own planet? Similar to a humans strength?

Also when Superman was held hostage in Zod's shit, he was handcuffed to a table. He obviously got super-weakened in the Kryptonian environment of the ship, but was he still stronger than the strongest human?

Is it this:

Human < Kryptonian on Krypton (red sun) < Kryptonian on Earth (yellow sun)

Or this?

Human = Kryptonian on Krypton (red sun) < Kryptonian on Earth (yellow sun)
gpt
If we go by the classic comic book explanation than an Kryptonians in their natural environment are physically equal to humans (mentally they are supposedly in a different league). However the movie has already distanced itself from the comics in this respect so we can't be sure. 

Based solely on what we see... eh... it's hard to tell. The annoying thing is that everyone we meet seems to have military training that could excuse how fast, strong and skilled they are in the opening sequence. What's more is that we don't know what the gravity was like on Krypton (although it appears Earth like). 

To answer your other queries based on Superman on Zod's spaceship, you'll notice that Superman is incredibly ill to the point that he can't ever stand, so even if he was stronger than your average human at this point it wouldn't matter since he wouldn't be able to use it.