How much ATP does the ATP-CP system yield?

The ATP-CP system, also known as the phosphagen system, is primarily responsible for providing immediate energy during high-intensity, short-duration activities, such as sprinting or heavy lifting. This system utilizes adenosine triphosphate (ATP) and phosphocreatine (CP) stored in the muscles to replenish ATP quickly without the need for oxygen.

In terms of energy yield, the ATP-CP system generates one molecule of ATP per molecule of phosphocreatine that is broken down. Since the primary goal of this system is to supply quick bursts of energy rather than a large volume of ATP, this 1:1 ratio leads to a very limited yield, typically considered to be less than one ATP molecule in terms of the energy available for longer-duration or endurance activities.

Therefore, the answer indicating that the yield is less than one is accurate when considering that the ATP-CP system's primary function is not to produce a large amount of ATP, but rather to facilitate instantaneous energy release for short, explosive activities, making this yield characteristic of the system.