Changes in the FDP (fibrin and fibrinogen degradation products) value under mental and physical stress. I. Changes in FDP and other indices of physio-biochemical effects of stress loaded on volleyball players during training.

It has been known that CA change during physical exercises and associate with dynamic aspects of the coagulation fibrinolysis system of the blood. Therefore, we studied fibrin and fibrinogen degradation products (FDP) under physical exercises together with LDH, CPK, LA, CRE, Na, K and P. 1) College students of Department of Education majoring in sciences of physical education significantly increased activities of CPK and LDH during the training for volleyball games compared with the pre-training values. This increment was remarkable for those who exercised hard, that is, who were loaded with large physical stress. 2) Changes in LA were included in the range of its normal values. Freshmen who had not been trained much and consequently whose adaptability for physical stress was insufficient increased the LA level significantly relative to the pre-training level. 3) Although changes in P were included in the range of its normal values, significant increase was observed by physical stress. Examinations by individual disclosed that a tendency of changes in P was similar to that in CPK and FDP. 4) The tendency of changes in FDP agreed with that in CPK and P and an increase was observed for those who were loaded with large physical stress. It was further observed that especially for those who were loaded with large mental stress together with physical stress the increase in FDP was evident. Therefore, it has been suggested that FDP can be used as an index of biotic effects of not only physical stress but also mental stress.