According to a recent edition of Fitness magazine, the average person sitting through the average boring office meeting burns about 88.5 calories an hour — assuming they don't eat anything during the meeting.
People who fidget at meetings burn off a few more calories but irritate those around them. According to "The Food Bible," one average Pop Tart contains about 210 calories. So average person would need to sit through approximately 2 1/2 hours of average boring meetings to burn up one average Pop Tart.