Before they remove Sam from the tube, she was lying the opposite direction from when they opened it.
Amanda Tapping is 5'9", the guard was not a large man, so of course the clothes fit.
The bra comment is just odd. Does anyone wonder how O'Neill got boxers/tighty whities?
Original: "Captain Carter is seen to be naked whilst lying in the cryo tube. Colonel O'Neill tells her to take the guard's clothes. Not only does a man's clothes fit her perfectly, but she also manages to find a bra."