So after the last ramble there was a brief discussion about how accurate the calorie counters on things like stationary bikes or treadmills are. I was trying to explain the physics of calories but since I couldn’t remember exactly how the whole calories = a unit of energy thing works I probably just sounded mildly retarded. I still think it’s an interesting topic though so I’ll put forth some knowledge / trivia.

A calorie “approximates the energy needed to increase the temperature of 1 kg of water by 1 °C. This is about 4.184 kJ” -wikipedia. So if you were to take that candy bar and light it on fire under a beaker filled with a kilogram of water, then every degree that the water rises is equal to a calorie.

So my thought was if you are lifting a weight, it takes X amount of energy to move that weight. That much should be constant since were on earth with gravity. So I thought the same thing would apply to stationary bikes or elliptical machines. So every time you make a rotation on the elliptical it takes X amount of energy to push the machine through a rotation. I assumed that amount would be known by the manufacturer and they could then calculate the calories. But according to this article, I was wrong, those things aren’t accurate.

This is a basic explanation from wikipedia about how calories relate to fat:

Human fat tissue contains about 87% lipids, so that 1 kg of body-fat tissue has roughly the caloric energy of 870 g of pure fat, or 7800 kcal. Therefore one has to create a 7800 kcal deficit between energy intake and use to lose 1 kg of body-fat. (In U.S. customary units, that is about 3500 cal per pound.) [2] In other words, if you eat 3,500 Calories more than your body needs, you will put on about 1 pound of fat. If you use up 3,500 calories more than you eat, you will lose about 1 pound of fat. These approximations assume that there is no net gain or loss in muscle, which can also be built using food energy, or metabolized as a source of energy.

This calorie calculator can tell you how many calories you burn brushing your teeth. I don’t know how accurate it is though. It says that you burn more calories in a minute of brushing your teeth than you do in a minute of sex.

Here is some more pointless trivia:
Does drinking ice water burn calories?
How many calories does a person need daily?