Adobe premier cs5 help?

i have some footage. I have succesfully made the video by selecting the preference as 1080p. But now when i export the final video, the video isn't playing in full screen. There is a black thick border around it. When i play that video in my 1080p hd tv, the video is very small and it is at the center of the screen and there is a really huge thick border around it... i want to expand the video in hd so that it comes full screen......"my footages are all hd ones"....yet it is coming like that..?