📓 Physiological study in relation to exercise and actual physical demand during event is very important to critically understand physiological basis of performance. The fatigue causing factors workload, recovery pattern from fatigue etc. should be very specifically understood in real terms. Understanding this background, the research scholar took up research project to investigate in- depth and detailed Physiological responses of two Long distance running events 5000mts and 10,000mts.Research scholar being a University level athlete and having completed masters degree in athletics, the selection of area was most appropriate and natural choice.In this context in depth investigations on Physiological basis of long distance runners is crucially important for high performance training implications. In this respect identified two groups of parameters that were considered significant indicator and basis of aerobic as well as anaerobic capacity- Lactate response, Blood Glucose, VO2 max. , Respiratory rate, Heart rate and Lactate Dehydrogenase ( LDH) were chosen as the Indicators of physiological responses and fatigue of long distance runners.