The greater liver glucose output during exercise is due primarily to:Group of answer choicesincreased glycogenolysisreduced hepatic glucose extractionenhanced gluconeogenesis from lactate

The greater liver glucose output during exercise is primarily due to increased glycogenolysis.

Here's why:

1. Glycogenolysis is the process by which glycogen, a form of stored glucose, is broken down into glucose-1-phosphate and then converted to glucose-6-phosphate for use in energy production.

2. During exercise, the body needs more energy, and thus more glucose. The liver responds to this increased demand by breaking down its stores of glycogen into glucose through the process of glycogenolysis.

3. While both reduced hepatic glucose extraction and enhanced gluconeogenesis from lactate can contribute to increased glucose output, they are not the primary mechanisms.

4. Reduced hepatic glucose extraction refers to the liver taking less glucose out of the bloodstream, which would not increase the total amount of glucose available.

5. Enhanced gluconeogenesis from lactate refers to the creation of glucose from non-carbohydrate sources, such as lactate. While this can increase glucose output, it is a slower and less efficient process than glycogenolysis and is typically more active during longer periods of fasting or intense exercise.

So, the primary reason for the greater liver glucose output during exercise is increased glycogenolysis.