The author states that _______.

Heredity and health determine the top limits to which your physical capacity can be developed. This is known as your potential physical capacity. This potential capacity varies from individual to individual. Most of us, for example, could train for a lifetime and never come close to running a four-minute mile simply because we weren't built for it. The top level at which you can perform physically right now is called your acquired capacity because it has been acquired or developed through physical activity in your daily routines.