Defective meat causes economic losses for the meat industries. Biochemical changes occurring post mortem in meat depend, mainly, on the glycogen content. A post mortem non-converted part of glycogen that remains in muscles is called a residual glycogen. The residual glycogen affects the quality of meat. In the paper, the impact is presented of selected environmental factors on the glycogen content in muscles of slaughter animals. The structure of glycogen and its role in shaping up the meat quality are discussed. The factors are described, which impact the post mortem glycogenolysis. The effect is comprehensively discussed of physical activity, nutrition, pre-slaughter fasting, transport as well as of the treatment of animals prior to slaughter on the glycogen concentration in muscles. Those issues are included that refer to mental and physical stresses at various steps of pre-slaughter proceedings as is their effect on the metabolism of muscles and the reserves of glycogen in muscles. Furthermore, the effect is shown of chilling rate of carcasses after slaughter on the course and extent of post mortem glycogenolysis. In order to achieve a higher meat quality, it is required to take multidirectional actions in the domain of genetic selection, optimization of breeding conditions, and ante mortem treatment of animals.