Glycolysis generates two ATPs net per glucose whereas gluconeogenesis uses four ATPs and two GTPs per glucose. Thus, if both glycolysis and gluconeogenesis  were  allows  to  operate  concurrently,   converting  glucose  to back again   and  pyruvate the only net result  would  be the utilization  of two ATPs  and two GTPs, a so-known as futile cycle. This is avoided by tight coordinate regulation of gluconeogenesis and glycolysis. Since various of the steps of the two pathways are general, the steps which are distinct in every pathway are the sites of this regulation, in particular the interconversions between fructose 1, 6-bisphosphate   and fructose 6-phosphate and between PEP and pyruvate.