Abstract：This study aimed to investigate the correlation between long jump distance and various variables related to speed control before take-off in 2 different run-up distance conditions, and also to compare the differences in speed control variables between 2 run-up distances. This study recruited 9 male collegiate long-jump athletes, who had achieved top-eight rankings in national-level competitions in Taiwan. Each participant was asked to perform 9 trials of long jump under both half and full run-up distance conditions, and the speed in the last 10 m and motions of the last 2-steps before take-off were recorded using an electro-optical motion capture system. The imaging data were further used to develop speed control and motion characteristics data. The results demonstrated that moderate correlation existed between long jump distance and take-off angle for the full run-up distance condition. However, a high positive correlation was found between long jump distance and take-off angle, and a negative correlation was noticed in the speed change in the last 10 m before take-off for the half run-up distance condition. The univariate F-test revealed significant differences between those 2 run-up distances in take-off angle, maximum speed in the last 10 m before take-off, approach speed utilization rate, absolute utilization rate of approach speed, change in stride length 2 steps before take-off, and change in speed in the last 5 m before take-off. These findings indicated that the run-up speed and approach speed utilization rate were related with the long jump distance for the full run-up distance condition. Furthermore, a long jumper may increase the take-off angle and long jump distance with less loss of his horizontal velocity before take-off by reducing the length of the last stride before take-off. However, the take-off angle was related to the long jump distance in the half run-up distance. A high run-up speed before take-off may reduce the take-off angle and further decrease the long jump distance. (Full text)