The main issue is body composition (see the body fat calculator for more). Calorie expenditure will vary depending on the ratio of body fat to muscle or lean mass. NOTE that as our bodies adapt to exercise and our body composition changes - so will the amount of Calories burned.
The definition of a throttle is a valve that controls the fluid flow. An example of a throttle is a car part that controls how fuel moves through the system. Throttle is defined as to control the speed of an engine or the flow of fuel in an engine, or to hold down or choke.
The throttle (green) is a valve that swivels to open or close the pipe. When the throttle is open, more air and fuel flows to the cylinders so the engine produces more power and the car goes faster. The mixture of air and fuel flows down into the cylinders.