Originally posted by: Howard
Don't think so. When the body is idle, it uses less oxygen than you think.
Ah - but most people aren't very calm when they're in that type of situation, so they naturally not calm. They're more likely to start breathing heavily due to the adrenaline rush you receive while realizing the reality of the situation.
When I was 5 years old, I locked myself inside of the trunk of my parents Volvo while playing hide and seek. Needless to say, I stayed in it for 4 hours. It was in the winter, so overheating wasn't really a concern. Thankfully the trunk was a pass through (although I didn't fit through it). I remember hyperventilating after about two hours, and after 4 my neighbor heard me screaming (I had been screaming almost through the whole ordeal), called my mother (we lived on a military base, so she was close by), and came and unlocked the trunk.