A simple sleep & heat related question here..

[Raider]

Ok so it's 11pm, i'm watching TV in shorts, t-shirt, quite comfortable really. Not that hot.

11:30pm, strip down to just boxers, lie on bed with NOTHING on top of me, don't move a muscle, now i'm overheating!

Why the hell does this happen? How can wearing less clothes, and not moving result in more heat? Grrr damn you summer!!

 

[Raider]

Could it also be because when you're lying down your body is in contact with a large surface, thus trapping more heat? I need to sleep sitting up I think

 

[Raider]

In a flat, so everything is on the level here