Quote:
Originally Posted by Pretty Little Flower
The machine is not measuring how many calories you are expending. It is measuring, e.g., how many watts you produce, or what your MPH is. If I can hold 24 MPH on a spin bike for an 30 minutes without a major expenditure of effort, I am burning fewer calories than a person who needs to work really hard to hold that speed. Heavier people people burn more calories than lighter people do maintaining the same output (watts, MPH, however you are measuring it). Males and females burn calories differently. People who are the same weight but have different fat content and muscle masses burn calories differently. The treadmill has no idea how many calories it is taking you run X miles at Y MPH. It just knows that you did it and gives you a calorie burn based on something like what a typical 150 lb man would burn.
|
I feel like maybe I am missing something, and it may be because I never took physics, but let me try again.
The machine can measure how many watts you produce. Wikipedia tells me a watt is a unit of power, a measure of energy transferred per unit time. So if the machine can measure watts and time, you can derive energy. Calories are a measure of energy. So the machine should be able to measure calories of work performed. It is true that bodies will differ in terms of how efficiently they can mobilize the body's resources to convert them to do work. It is also true that it takes more energy to move a bigger body, but if you can input weight and it can calculate watts, doesn't that address that issue?
