Had the same issue with Emirates(in economy). There was a Japanese guy sitting directly behind me and he was massive, like a Sumo Warrior! I couldn't recline my seat even a millimetre because oh his size, which was agony for me as i had slipped on wet tiles in the hotel, doing my back in. The staff had no sympathy for my discomfort and when i made a written complaint to Emirates, their reply was akin to "tough". I have never flown with Emirates since. Qatar much superior in customer care.