BodyBug is a small tech device that can be strapped on to your arm and will measure the number of calories you are burning. Developed by BodyMedia, the gadget uses a patented procedure for calculating calorie burn called "sensor fusion." It works by collecting a series of data from the wearer's body including measurements of motion, the amount of heat dissipated by the body, galvanic skin response and skin temperature. It combines these factors with the user's specific body parameters such as age, gender, height and weight to produce and accurate reading.

The Bodybugg has an online interface that enables the user to connect the device directly to a computer. The Bodybugg software can then calculate how many calories have been burned and how many are still available for consumption relative to the individual weight management and fitness goals of the user.

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• DirectLife