Compression was effected by a compression field which allowed the Slitheen to inhabit skin suits made from humans, though this caused gas exchange leading to farting. (TV: Aliens of London [+]Loading...["Aliens of London (TV story)"])
The Abzorbaloff used a limitation-field creator which kept him compressed after he absorbed his human victims. (TV: Love & Monsters [+]Loading...["Love & Monsters (TV story)"], PROSE: Doctor Who: The Encyclopedia [+]Loading...["Doctor Who: The Encyclopedia (2007 reference book)"])