Muscle cell activity increases and ATP decreases below the set-point, a sensor molecule detects low ATP and activates protein kinase A, protein kinase A activates protein kinase B, protein kinase B activates transporters that absorb glucose into the cell, glucose is metabolized. This is a _________.

Feedback mechanism is the body's way of maintaining physiologic processes in the body. These physiologic processes include maintaining homeostasis, production of energy, hormones as well as enzymes required for chemical reactions.

There are 2 types of feedback mechanism:

Positive feedback: The stimulus (message) sent to the brain, produces prolonged increased production or increased activity in the body.
Negative feedback: In negative feedback, the stimulus causes production, secretion or activity till a set point where the body knows it has taken enough. This causes a self termination of the process.

In the increased muscle activity, the increase in activity in turn causes a decrease in energy (ATP) and serves as the stimulus leading to the release of enzymes which in turn lead to increased absorption of glucose which will be used by the body to produce more ATP needed for the muscular activity. At the end of the muscular activity, the body recognizes that it doesn't need an increased absorption of glucose to support increased activity anymore and glucose absorption normalizes.