Question

How will a healthy individual’s ATP production change during an eight-hour fast?

The individual’s ATP production will decrease significantly.
The individual’s ATP production will increase significantly.
The individual’s ATP production will not change significantly.

Answer 1

During an eight-hour fast, a healthy individual's ATP production will not change significantly. After about 8 hours of fasting, the body shifts from using glucose as its primary energy source to utilizing stored glycogen and eventually fat stores. While there may be adjustments in the pathways used for ATP production (such as increased fatty acid oxidation), the overall capacity for ATP production remains relatively stable in healthy individuals.

However, if the fast were extended beyond this timeframe, there may be more noticeable long-term metabolic changes. But for an eight-hour fast, the overall effect on ATP production is minimal.