The swimming records were analyzed in order to grasp the actual situation of the swimming races in Japan which has been hanging low. The means was to collect the world and the Japanese men\u27s and women\u27s records of free style events (100m-1500m) in 1978 and the records of free style events (100m, 200m, 400m) in these thurty years. Comparison of the swimming speed and distance; the connection between distance and the time required in 1978 were studied. The transition of the records between the world and the Japan in these thirty years was studied. The follwing results were obtained by analyzing the accumulated data : 1) Speed per second; The Japanese records of middle free style swimming events are much the same with the world records of long free style swimming events. 2) Decline of swimming speed with distance; Japanese women\u27s records are inferior to those of the world in every free style swimming. 3) Transition of the records of the world and the Japan in these thirty years; Japanese men\u27s records are inferior to world record, and women\u27s records are superior to world record. 4) Japanese women\u27s records in the past years show the bigger transition than the world records. 5) On the basis of above-mentioned findings, the records of the swimming in Japan has been declining rapidly since Tokyo Olympic. There is the difference of thirteen years between the records of Japanese men and those of the world men, and twelve years between the records of Japanese women and those of the world women
