In muscles, how many ATPs are produced from the conversion of one glucose residue in the linear chain of glycogen to lactic acid i.e ,anaerobic glycolysis ?

In any cell or tissue other than muscle, glycogen give rise to glucose which is phosphorylated by hexokinase to glucose-6-phosphate using ATP and then undergo fuher glycolysis. However, Muscle lacks glucose-6-phosphatase which conves glucose-6-P produced for glycogen to glucose in other cells. So, the glucose-6-phosphate formed in glycogen degradation in muscles can directly enter the glycolysis without the need for ATP-requiring hexokinase reaction (See fig above). Thus, one less ATP is required for the investment stage of glycolysis in muscles only. Hence, net yield of ATP increases by 1. If staing material is ATPs Obtained glucose 2 ATPs glucose-6-phosphate 3 ATPs