TECHNIQUE ANALYSIS OF THE BACK TOSS ON THE PARALLEL BARS PERFORMED BY ELITE GYMNASTS

The back toss (BT), a skill frequently performed by gymnasts on the parallel bars (PB), involves a release-regrasp swing type of motion from a handstand to a handstand position. Mastering the skill is beneficial not only for points awarded to gymnasts by the judges for the skill itself but also for its contribution towards the perfect execution of other PB skills including the most current1 PB dismounts. The purpose of this study was to: I) identify the skill variables best correlating with the scores given to the BTs by qualifying judges, and 2) to identify the differences in technique between the most and least skillful BTs. Seventeen BTs, recorded during the 1990 United States Gymnastics Federation Championships with a NAC 400 HSV camera operating at 200 Hz, were analyzed utilizing the Arid Performance Analysis System (APAS). Two dimensional position data of 4 (for BTs without knee or elbow joint flexion) to 6 (BTs with elbow and/or knee joint flexion) body points were digitally smoothed before being submitted to further analysis. Product moment correlations between mechanical variables and the scores given to the BTs by qualifying judges, indicate that the best predictors of a good score are the shoulder joint angle at regrasp (p = .001), the time the gymnasts were airborne (p = .021), the horizontal velocity of the center of gravity (COG) at release (p = .022), the hip joint angle at release (p = .025), the hip joint angle at release and the minimum hip joint angle (p = .025 and .048, respectively), the normalized maximum height of the COG above the bar (p =.028), the greatest total angular momentum (p = .035), and the shoulder joint angle at release (p = .054). Paired t tests between variables of the most (N=8) and least (N=9) skillful BTs indicate that the discriminating factors are the hip joint angle at release (p = .03), the shoulder joint angle at regrasp (p = .032), time from the smallest hip joint angle to zero degrees of anterior shoulder joint angle (p = .049), and the horizontal velocity of the COG at release (p = .058). Additional factors differentiating the best and worst BTs studied are the time from zero degrees of anterior shoulder joint angle to release (p = .06), and the shoulder joint angle at release (p = .066

MECHANICAL ANALYSIS OF THE INVERTED GIANT SWING

Strength, balance, flexibility, speed, proper timing, and stamina have long been considered a necessity for the sport of gymnastics. However, the explosive worldwide development of the sport the last decade established another factor --the mastering of swinging --to be of paramount importance for gymnasts desiring to succeed in competition. Among the different kinds of swings, the giant swing refers to those gymnastic skills which require a full 360 degree rotation of the gymnast's suspended body about a relatively fixed point. Depending on the direction of the rotation, the gymnast's body configuration and the type of handgrasp, the degree of difficulty for the various types of the existing giant swings ranges from low to high. With reference to the horizontal bar, the forward and backward giant swings are considered, for example, fundamental but of low difficulty, whereas the so called "inverted" and "German" giant swinqs are given high marks for difficulty

SHOULDER JOINT TORQUES AND THE STRAIGHT ARM/FLEXED HIPS PRESS HANDSTAND ON THE PARALLEL BARS

The recent rapid growth of the sport of gymnastics may be based, among other factors, on its versatility. Gymnasts attempt to win points in each of the various events by combining certain skills into spectucular eye pleasing routines. However, while the sport's governing body gives the athlete considerable freedom to choose or develop the appropriate skills for a particular routine, it also imposes certain restrictions. One of those restrictions is that routines on the floor, rings, and parallel bars should include a press handstand, i.e. a gymnastic skill requiring the slow elevation of an individual's body from an initial (usually an "L") stationary position to a handstand position. Several variations of press handstands exist depending on body configuration between initial and final positions. One of them, the straight arms/flexed hips press (SAFHP), is the variation most commonly used by gymnasts, and is depicted in Figure 3 (see results)

Technique Analysis Of The Kip On The Parallel Bars Perfonned By Elite Gymnasts

Within the sport of gymnastics, where hundreds of skills exist, few movements could be considered fundamental. The kip, performed frequently on several apparatuses by both male and female gymnasts, is one of the fundamental skills. With obvious resulting benefits in improving performance, increasing efficiency of performance and decreasing the incidence of injuIy, one would expect extensive study of the skill in question. Review of the literature, however, reveals that the related research is limited and confined to either the kip on the high bar or on the uneven bars. The kip on the parallel bars, chosen as a required skill in compulsory competition, has .not yet been studied. Although similarities between the mechanics of the kip in all apparatuses would be expected, the similarities cannot be conclusive until relative data becomes available. It was, thus, the purpose of this investigation to study the mechanics of the kip on the parallel bars and to identify the differences in technique between the most and least skilful kips. Thirty seven kips, recorded during the 1990 Winter Nationals and 1990 United States Gymnastics Federation Championships with a NAC 400 HSV camera operating at 200 Hz, were analyzed utilizing the Ariel Performance Analysis System (APAS). Two dimensional position data of 4 (for kips without knee or elbow joint flexion) to 6 (kips with elbow andlor knee joint flexion) body points were digitally smoothed before being submitted to further analysis. Results indicate that in addition to differences in the magnitude of several of the kinematic variables studied (segmental angles to horizontal, shoulder and hip joint intersegmental angles and angular velocities, center of mass displacement and velocity), timing differences between the most and least skilful kips in joint and segmental motion exist. Furthmore, there are indications that the timing differences between the kips might be more critical than the differences in magnitude

A KINEMATIC ANALYSIS OF JERK TECHMQUE IN OLYMPIC WEIGHTLIFTING

It has been reported that the majority of failures in the performance of the clean and jerk lift in weight lifting competition, including the Olympic Games, are due to unsuccessful jerks. In an attempt, therefore, to determine the reason(s) of the poor rate of success in jerk, successful (2) and unsuccessful (I) jerks performed by a highly skilled weight lifter in a competition environment were kinematically analyzed. Three lifts (including an American record, and an unsuccessful attempt), performed at the 1988 U.S. National Weightlifting Championships, were videotaped at 60 Hz and analyzed utilizing an Ariel Performance Analysis System (APAS). Two dimensional position data of 14 body points and the center of both ends of the barbell were digitally smoothed before being submitted to further analysis. The results revealed that the successful American record lift was characterized by greater duration, barbell displacement and knee, hip and ankle joint flexion during the dip or half-squat phase of the jerk. In addition, in the unsuccessful American record attempt, the bar was driven forward substantially more than the two successful lifts. and the hip, knee and ankle joint angles in the split-squat position were smaller than in the successful lifts. A large sample of successful/unsuccessful trials must be studied before definite conclusions regarding the reasons for success/failure are reached

GAYLORD II: A QUALITATIVE ASSESSMENT

In the process of awarding points, judges look at several elements in gymnast's routines. Among them, the element of risk weighs more heavily now than just a few years ago. Today's gymnasts do not expect to win in international competition by only including in their routines skills of moderate difficulty, even if those skills have been executed with maximum amplitude and expression. To win today the gymnast is required to be inventive and to definitely take more risks than a few years ago. As a result, a plethora of new skills is added constantly to the vast number of existing movements

The Karate Reverse Punch - Technique Comparison Between Two Different Styles

The purpose of this study was to compare the movement patterns of the reverse punch executed according to the traditional Tae Kwon Do (TKD) style to a sirnilar punch executed in the modern Choi Kwang Do (CKD) style. Four males, two from each style, who had attained the rank of black belt were videotaped with two NAC 400 HSV cameras operating at 200 HZ while punching against a Kistler force plate. Three dimensional coordinates of seven body points were calculated by combining the images of the two cameras utilizing the direct linear transformation (DLT) method. The raw position data was smoothed with a cubic spline function before being submitted to further analysis. It was found that very different movement patterns existed between the two styles. The CKD punch was delivered with more sequential acceleration and deceleration of the body segments segments than the TKD punch. It also showed larger displacements of the knee, hip, shoulder, elbow and wrist joints and registered higher impact forces. The CKD punch which registered the greatest peak resultant force per unit of body mass displayed the most sequential movement, greatest joint peak velocities, greatest velocity of the wrist at impact and largest combined joint displacement. It was concluded that the reverse punch executed according to CKD style conforms more closely than a similar punch executed in the TKD style to the ideal (sequential) movement models outlined in the literature. As a result, the CKD punch is more effective since higher impact forces are generated

A COMPARATIVE ANALYSIS OF THE TRIPLE BACKWARD SOMERSAULT AND THE DOUBLE BACKWARD SOMERSAULT ON THE HIGH BAR

Both the triple backward somersault in tuck position (TBS) and the double backward somersault in layout position (DBS) are considered the most difficult dismounts on the high bar. Although similarities and differences between TBS and DBS would be expected, they cannot be conclusive until relative data are compared. It would be beneficial for gymnasts and coaches to recognize the differences between TBS and DBS for performing both skills perfectly. The purpose of this study, therefore, was to investigate the differences between variables of the TBS and DBS. Five TBS and five DBS recorded during the 1990 United States Gymnastics Federation Championships with a NAC 400 HSV camera operating at 200 Hz, were analyzed utilizing an Ariel Performance Analysis System (APAS). Two dimensional position data of 6 body points (ankle, knee, hip, shoulder, elbow, and hand) were digitally smoothed before being submitted to further analysis and kinematic and kinetic data were compared. Paired t tests (