Question

Patients with an inherited deficiency of phosphorylase in skeletal muscle (McArdle disease) have decreased ability to derive energy from which of the following?

1) Glycogenolysis
2) Glycolysis
3) Beta-oxidation of fatty acids
4) Krebs cycle

Answer 1

Patients with McArdle disease have a reduced ability to perform glycogenolysis due to a deficiency of muscle phosphorylase, impairing rapid glucose mobilization and energy production.

Step-by-step explanation:

Patients with an inherited deficiency of phosphorylase in skeletal muscle (McArdle disease) have a decreased ability to derive energy from glycogenolysis. This is because muscle phosphorylase is crucial in breaking down glycogen into glucose-1-phosphate, which can then be transformed into glucose-6-phosphate and enter glycolysis. The inability to perform glycogenolysis effectively means that these patients cannot quickly mobilize glucose from glycogen stores, leading to a reduced capacity for energy production during high-intensity exercise when rapid glucose availability is crucial.