Venison that comes from a deer that is shot before it can run is more tender and not as strongly flavored as venison from a deer that has run to exhaustion. Why?
Exercise, like being chased, puts a high energy demand on the body. You needed ATP to power the contraction of sarcomeres by myosin that lead to muscle contraction. The first step in producing ATP is glycolysis. However, glycolysis only produces a limited amount of ATP (2 ATP and 2 NADH = 2+2x3= 8 ATP). For more ATP you need to enter into the Kreb's cycle (or citric acid cycle). From the ...
A detailed description of lactic acid in deer involving glycolysis and Kreb's cycle descriptions. Contains web links.