For those of us who spend the best part of our day hunched over a keyboard starting at a computer screen, any physical exertion—however small—has to go some way towards constituting exercise. So how many calories does a mouse click burn?


Yahoo Japan reports that a recently published book, Convert Anything to Calories, has seen a scientist work out how many calories are burnt with each and every mouse click.

Based on a typical index finger having a volume of 10.8 cubic centimeters and weight of 11.7 grams, it it should require 16.7 micromoles of ATP (Adenosine triphosphate, the molecule that transports energy in cells) to move one gram of the body for one second. Converting that quantity of ATP into burned calories for the whole finger—there are 7.3 calories in one mole of ATP energy—a single mouse click should, in theory, burn 1.42 calories.


Now the for the bad news: an annotation to the math adds that "the calculation assumes the muscle contracted completely, so the actual amount of calories used is a little less." Dammit. Still, if you do manage to use your mouse energetically enough, at a rate of 1.4 calories a click you can burn off a Big Mac in 350,000 presses. Get clicking! [Yahoo Japan via Rocket News 24 via TechCrunch]

Image by Paolo Signorini under Creative Commons license