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Yoshiaki Takei

The purpose of this study was to determine mechanical factors, through development of the deterministic model, that govern successful performance of the handspring vault. The subjects were 40 elite male gymnasts participating in the 1987 Pan American Games. A motion-picture camera placed with its optical axis at right angles to the runway was used to record the subjects’ performances. Significant correlations indicated that the following were important determinants for success: (a) large horizontal velocity and angular momentum at takeoff from board, (b) shorter time of preflight and smaller relative height of takeoff in preflight, (c) large horizontal breaking force and large vertical force exerted as well as a large loss of angular momentum during horse contact, and (d) large vertical velocity of takeoff from horse. Significant correlation of “on-horse” factors with the judges’ scores indicated that the more the gymnast focused on horse contact and the more vertical the direction of his effort at takeoff, the better the final result. A significant negative correlation revealed that the less the height of CG at touchdown on mat, the more points awarded by judges. This relationship was almost entirely a consequence of the landing angle.

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Yoshiaki Takei

The purposes of this study were (a) to determine the mechanical factors associated with successful performance of women’s handspring vault and (b) to contrast the findings to those of men to gain insight for improvement of performance. The subjects were 24 female gymnasts in the 1987 Pan American Games. Significant correlations indicated that the following were important determinants for successful results: (a) large horizontal velocity (VH) and distance of hurdle; (b) large vertical velocity (Vv) at touchdown (TD) on board, a large change of Vv on board, and a short time of board contact; (c) large VH and Vv at takeoff (TO) from board; (d) short time of horse contact; (e) large VH and Vv at TO from horse; (f) high body CG at TO from horse; and (g) great distance and height and a long time of postflight. Comparisons revealed that women had significantly smaller VH and Vv at TD on horse and departed from it with significantly smaller VH and Vv than men. This resulted in significantly less height and distance as well as a shorter time of postflight for women even after adjusting for horse height and subject physique.

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Yoshiaki Takei

The purpose of the study was to identify mechanical variables that govern successful performance of the handspring with full turn vault. Subjects were 67 male gymnasts from 25 countries performing the vault during the 1992 Olympic Games. The vaults were filmed by two 16-mm Locam II DC cameras operating at 100 Hz. Approximately 80 frames per subject were digitized for each camera view. Direct linear transformation (DLT) was used to calculate the 3-D coordinates of the digitized body points. The method of Hay and Reid (1988) was used to develop a theoretical model to identify the mechanical variables that determine linear and angular motions of the vault. Significant correlations (p < .005) indicated that the following were important determinants for success: large horizontal velocity, large horizontal kinetic energy term, and overall translational kinetic energy term at takeoff from the board; short duration, small vertical displacement of the center of gravity (CG), and small somersaulting angular distance of preflight; large vertical velocity and large vertical kinetic energy term at takeoff from the horse; and large "amplitude of postflight," that is, large horizontal and vertical displacements of CG and long duration of flight; great height of CG during the second quarter-tum in postflight; and small point deduction for landing.

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Yoshiaki Takei

The purpose of this study was to determine the mechanical factors that govern success in the performance of the handspring and salto forward tucked vault. The subjects were the 41 all-around gymnasts participating in the 1986 USA Gymnastics Championships. A motion-picture camera placed with its optical axis at right angles to the runway was used to record the performances of the subjects. Significant correlations indicated that the horizontal velocity at takeoff from the board was an important determinant for successful results, and also that the more the gymnast’s focus was on horse contact or blocking and the more vertical the direction of his effort at takeoff into the postflight, the better the final result. Quite unexpectedly, significant correlations revealed that the greater the relative height of takeoff from the horse and the less the height of CG at landing on the mat, the greater the points awarded by the judges. These relationships were almost entirely a consequence of the landing angle. Rationale for these findings were based on close observations of the filmed performances and the correlational analyses.

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Yoshiaki Takei

It was hypothesized that the techniques employed by two groups of male gymnasts in performing the handspring and salto forward tucked vault at the 1988 Olympics were not significantly different. The 11 highest scored vaults (Gl) of the 51 subjects filmed during the competition were compared with the 11 lowest scored vaults (G2). The G1 had (a) significantly greater horizontal velocity of hurdle and preflight and (b) significantly greater vertical reaction forces exerted on them by the horse, which in turn produced a significantly greater change of vertical velocity while on horse. Consequently, the better gymnasts departed from the horse with significantly greater vertical velocity, which resulted in significantly greater height, larger distance, and longer time of postflight than the gymnasts in G2. The better gymnasts had the instant of the tightest tuck position while significantly nearer the instant of peak postflight than the G2 gymnasts, which caused the height of CG at the tightest tuck position to be significantly greater for the better gymnasts. During the subsequent phase of the vault, the better gymnasts moved out of the tuck position higher in midair, extended the body more fully, and held this extended position longer to a controlled landing on the mat, all of which the judges are seeking.

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Yoshiaki Takei

This study compared the techniques used by elite male gymnasts in performing blocking or pushoff against the horse and postflight in the handspring and salto forward tucked vault. Forty-one American gymnasts were compared with 51 Olympic gymnasts on the mechanical factors governing the blocking and body control for salto forward and kickout in postflight. A 16-mm high-speed camera recorded the performance of the gymnasts during the 1986 USA Gymnastics Championships and the 1988 Olympic Games. The results indicated that Olympic gymnasts assumed the tightest tuck position significantly nearer the peak of the parabolic path of CG and thus achieved significantly greater height of CG at the tightest tuck position during the somersault than did the U.S. gymnasts. The superiority of body control by the former after the tightest tuck to landing was evidenced by significantly longer time, larger horizontal and angular distances, greater average moment of inertia, and smaller angular velocity.

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Yoshiaki Takei

The purpose of this study was to identify the mechanical factors that are crucial to successful performance of blocking and body control for salto forward and kickout in the handspring and salto forward tucked vault. A 16-mm camera operating at 100 Hz was used to record the performances. The subjects were 51 male gymnasts participating in the 1988 Olympic Games. It was hypothesized that some mechanical factors identified in the model were significantly correlated with successful performance of blocking and body control for salto forward and kickout as rated by the judges. Significant correlations indicated that a large horizontal velocity at touchdown on horse is an important prerequisite for effective blocking and subsequent performance of postflight. The results also indicated that the body’s moment of inertia should be minimized by assuming the full tuck position just before or near the peak of flight, which maximizes the time and height available for executing the kickout in midair. The small angular speed of body rotation due to early kickout and the long-held extended body position as it travels a large horizontal distance are not only effective in the expression of artistic amplitude for virtuosity points but are also crucial for control in landing.

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Yoshiaki Takei

The purpose of the study was to determine the mechanical variables that are related to successful post-flight somersaulting performance of the Roche vault. The 23 Roche vaults performed during the 2000 Olympic Games were filmed by a 16-mm camera operating at 100 Hz. The 2-D direct linear transformation technique was used for spatial calibration. Approximately 60 frames were digitized per vault. The method of Hay and Reid (1988) was used to develop a deterministic model to identify the mechanical variables that govern linear and angular motions of the vault. Correlational analysis was used to establish the strength of the relationship between the mechanical variables identified and the judges’ scores. Significant correlations indicated that the higher judges’ scores were negatively related to five mechanical variables and positively related to seventeen variables in the model. The normalized horizontal displacement of body center of mass (CM) from the knee grasp to the peak of post-flight was the best single predictor of the judges’ score and accounted for 50% of variation in the judges’ score. Finally, the landing point deductions and the official horizontal distance of post-flight collectively accounted for 86% of the variance in the judges’ scores.

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Yoshiaki Takei and Eay Jin Kim

The purposes of this study were to (a) determine the mechanical factors associated with successful performance of the handspring and salto forward vault at the 1988 Olympic Games, and (b) contrast the findings in this study to those from the 1986 USA Championships to gain additional insight for the improvement of performance. The subjects were 51 male gymnasts in the 1988 Olympic Games. Significant correlations indicated that the following were important determinants for successful results: (a) large horizontal velocity (VH) at takeoff (TO) from floor and board resulting from a fast sprint in the approach run; (b) a large change of vertical velocity (Vv) during the horse contact by means of blocking with arms and shoulders; and (c) large VH and Vv at TO from horse, which ensures great distance and height and a long time of postflight, which the judges are seeking. Comparison of the techniques between the two groups revealed that the Olympic gymnasts achieved significantly greater horizontal velocity in preflight, change of vertical velocity while on horse, and vertical velocity at takeoff from horse, which resulted in a significantly longer time of postflight than for the USA gymnasts. An analysis of the aspect of form in postflight, possibly by means of mechanical variables, should be conducted because it may provide additional insight for improvement for performance of this vault.

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Yoshiaki Takei, Hiroshi Nohara and Mamoru Kamimura

The purpose of this study was to identify the mechanical factors that are crucial to a successful double salto backward tucked dismount from thehorizontal bar. The subjects were 35 American and 43 Japanese gymnasts competing in their respective 1990 national gymnastics championships. A 16-mm camera, placed with its optical axis parallel to the horizontal bar and operating at 100 Hz, was used to record the performances of the subjects. Significant correlations indicated that a large vertical velocity at bar release, which ensures great height and long time of flight, is important. Successful performance is also likely when efforts are made to (a) achieve the tightest tuck position during the salto backward near the peak of flight, (b) extend the body rapidly and fully early in rotation before the vertical body position is reached well above the bar, (c) maintain the extended body position during the remainder of the flight to display body style for virtuosity bonus points, and (d) simultaneously prepare for a controlled landing on the mat.