The aim of the study was to determine the mechanical variables that govern success of the handspring and double salto forward tucked (Roche) vault. Twenty-three Roche vaults performed at the 2000 Olympic Games were filmed using a Locam Ⅱ DC 16-mm motion picture camera operating at 100Hz. Approximately 85 frames were digitized for each vault analysed. The method of Hay and Reid (1988) was used to develop a theoretical deterministic model to identify the mechanical and physical variables that govern linear and angular motions of the vault. Correlational analysis was used to establish the strength of the relationship between the causal mechanical variables identified in the model and the judges' scores. Significant correlations (p ＜ 0.065) indicated that the following were important determinants of success: large normalized average vertical force exerted on the board and short time of support on the board; large resultant velocity at take-off from the board; large horizontal and resultant velocities and high body’s center of mass (CM) at take-off from the horse; and large relative height of take-off of post-flight and high body CM at touchdown on the mat. Of the 6 significant variables identified as determinants of success of the Roche vault, [the normalized vertical force on board, the horizontal velocity at take-off from the horse, and the height of CM at touchdown on the mat] collectively accounted for 58% of the variation in the judges' scores.

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There has been no research examining the throw distribution of baseball pitchers. We investigated the throw distributions when a batter was absent and when the standing positions of batters were changed. Subjects were four baseball pitchers. All subjects were right-handed and pitched overhand from the mound to the target. Subjects threw under four conditions, 1) Control (C); a batter was absent, 2) Right Near (RN); a right batter stood near to the target, 3) Right Far (RF); a right batter stood far from the target, 4) Left (L); a left batter stood. The throw distribution was evaluated by the shape of the ellipse of constant distance and coordinates at the throw position. Under condition C, the throw distributions of all subjects were ellipses and their major axes were inclined clockwise (from the pitchers view). These results suggest that the clockwise inclination of the throw distributions were due to the orbits of the right arms' movements of the pitchers. In the condition RN, three subjects threw a ball lower compared to the other conditions and the upper right part of their ellipses which was observed under the other conditions was absent. The results in the condition RN might be due to the psychological conditions of the pitchers that they avoid hitting a batter by a pitch. It is considered that these results would be useful for baseball coaching.

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The purpose of this study was to acquire biomechanical data related to the physical act of jumping to intercept a high pass in the game of basketball. Six male basketball players volunteered to take part in this study. They performed two types of vertical squat jumps (SJ), from the starting positions, with the hands up (upSJ) and hands down (downSJ), and two types of vertical countermovement jumps (CMJ), from the starting positions, with their hands up (upCMJ) and hands down (downCMJ). They performed each jump condition seventeen times initiated by reaction to visual stimulus as quickly and as high as possible. The height of the jump was lowest in the upSJ condition. The height of the jump in the downSJ condition was not significantly different from both the CMJ conditions. The total reach time (time from the onset of visual stimulus to the time when subjects reached their peak during a jump) in the SJ conditions were significantly shorter than the CMJ conditions. Time when subjects reached 10cm from dactylion height over their heads in the upSJ condition was the shortest, and the time in the downSJ condition was the second shortest. The results suggest that it is important to take squat conditions (“stay low”) when a basketball player is required to jump as quickly and high as possible.

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The purpose of this study was to examine the effects of sports mental training (SMT) focused on technical coaches. In case l, a SMT was performed on a high school baseball team by a technical coach of the baseball team. A content of the training was a basic psychological skill like the goal setting. Levels of psychological competitive ability were assessed by the Diagnostic Inventory of Psychological- Competitive Ability for Athletes (DIPCA) before and after the training. As a result, the training improved the confidence and strategy ability of the baseball players. These findings suggested that combination of the SMT and the practice for technical skills was effective for the confidence and strategy ability. In case 2, we assessed effects of a SMT for a high school volleyball team and its technical coach. As a direct approach method, the SMT was performed on all the players by a SMT coach once a month. Moreover, as an indirect approach method, the SMT was performed on the technical coach by the SMT coach everyday. As a result, the team was 3rd place in Kinki competition tournament. A style of coaching in the technical coach was changed. Although a next goal had been lost when losing a match before the training, the technical coach set the goal of the team again, aiming at the Kinki competition tournament. The team switched the feelings from the lost game. Moreover, a remarkable improvement of psychological skill was seen in confidence and strategy ability for technical coach. Therefore, these results suggested the effects of SMT by technical coach and the effects of SMT for technical coach.

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