A piece of good news for all the Olympic enthusiasts out there - by just sitting on your couch and watching the games on TV or live, you burn 1.3 to 1.5 calories per minute.
However, your favourite Olympian on the screen is probably burning up to 20 calories a minute, said researcher Dr Michael Joyner.
For a typical workout routine for high calorie-burning sports like distance running or cycling , this can come up to 4,000 to 6,000 calories per session.
To put things into perspective, the recommended calorie intake for a normal person hovers around the 2,000 range. That means that the combined calorie intake of your full day's meals will only last an Olympian just a couple of hours!
This explains why an Olympian athlete ends up consuming upwards of 10,000 calories a day to replenish their body fuel supply.
In addition, with more muscle making up their body mass than us average humans, top-class athletes also end up burning more calories by just sitting at a desk, reading a book or watching TV, said physiologist Amy Knab, Ph.D..
While top-class athletes can get away with gorging on entire cheese pizzas (about 2,000 calories), a pint of Ben & Jerry's cheesecake-brownie ice cream (1,000 calories) or pasta drizzled with olive oil (about 800 calories), sadly not so for us.
As the London Olympics 2012 comes to an end, why not take a page out of our favourite Olympians and try an activity or two?
The below gallery compiles data from hundreds of BodyMedia Armband wearers to paint a picture of how many calories a normal person can expect to lose playing an Olympic sport.