As mentioned in another slip up on this move, it is true that a one does not bloat and swell as portayed. But, If you will notice when both Arnie and the bad guy are outside in the Martian atmosphere, they are both gasping for breath. Several times they both inhale and then croak labored screams and gasps.

This could not happen.

The pressure outside on the surface is much lower than the pressure inside the human body. So, they would let one sudden gasp as the air is taken from their lungs by the outside lack of pressure, but they, neither one of them would be able to take a second breath to utter the afformentioned dramatic gasps and croaks.