Hans: I am Hans.
Franz: And I am Franz.
Both: And we are here to PUMP! *clap* YOU UP!
Hans: Ja, ve vill pump up that girly-man!
Franz: Look at my bulging muscles!
Yes, but there is gravity in space -- it is just very weak because of the inverse square nature of the force of gravity. Also, the weight still has all of the inertia that it would otherwise have, making it just as hard to move.