Fuel reserves, rates utilization

Table I. Fuel Reserves and Rates of Utilization under...

Under normal conditions, the processes shown in Figure 3-2 are tightly coupled, so that the oxidation of metabolic fuels is controlled by the availability of ADI which, in turn is controlled by the rate at which ATP is being utilized in performing physical and chemical work. Work output, or energy expenditure, thus controls the rate at which metabolic fuels are oxidized, and hence the amount of food that must be eaten to meet energy requirements. As discussed in section 5.3.1, metabolic fuels in excess of immediate requirements are stored as reserves of glycogen in muscle and liver and as fat in adipose tissue. 

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