An allosteric enzyme that regulates glycolysis by catalyzing the transfer of a phosphate group from ATP to fructose-6-phosphate to yield fructose-1,6-bisphosphate. In humans, phosphofructokinase-1 in muscle exists as the homotetramer of M subunits. Defects in this muscle enzyme cause glycogen storage disease type vii, also known as Tarui's disease.