Energy expenditure factors determining

Physiological factors determining cardiac energy expenditure... 

The amount of stored fat depends on the level at which a balance is achieved between the rates of its deposition and mobilization and it has been suggested that each person has a physiologically determined set point at which energy intake and energy output are balanced. This is open to question but nevertheless it is necessary to consider the factors which control food intake, energy expenditure and the means by which they are balanced. 

The intake of ruminants in their natural habitat (i.e. at pasture) is influenced not only by the chemical composition and digestibility (or rate of digestion) of the pasture herbage but also by its physical structure and distribution. The grazing animal has to be able to harvest sufficient herbage to meet its needs without imdue expenditure of energy. Its intake is determined by three factors bite size (the quantity of dry matter harvested at each bite), bite rate (number of bites per minute) and grazing... 

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