15 research outputs found
PREDICTORS OF HORIZONTAL VELOCITY IN THE TAKEOFF OF THE LONG JUMP
Of the four types of jumping events in track and field (long
jump, triple jump, high jump, and pole vault), the approach for the long jump and triple jump is a purposeful preliminary to the projection of the body for horizontal distance. Collegiate athletes are often asked to perform in multiple events because ofthe importance of team scoring.
A common two event combination is the long jump and triple jump since both events' prime objective is to project the body for maximum horizontal distance. Although takeoff technique differs between the two events, the long jump and triple jump combination share horizontal velocity as the most important parameter in determining the distance achieved (Adams, 1975; Bosco, 1976; Brancazio, 1984; and Kreighbaum and Barthels, 1985)
RELATIONSHIP OF BIOMECHANICAL AND PSYCHOLOGICAL PARAMETERS BETWEEN PRACTICE AND COMPETITION IN POLE VAULTING
The purpose of this study was to examine relationships of biomechanical parameters, cognitive anxiety, somatic anxiety, and self confidence changes between competition and practice in the pole vault. Seven pole vaulters were videotaped in practice and competition and completed the Competition Sport Anxiety Inventory-2 (CSAI-2). A Pearson Correlation was computed to examine relationships between the difference score of the means for the competition and practice vaults of all the parameters. Several significant correlations were found (
KINEMATIC ANALYSIS OF AN ELITE LEVEL FENCER
PURPOSE The purpose of the study was to provide a kinematic analysis of the lowerlimb motion during an actual fencing bout. Specifically, the lunge and certain movements preceding the lunge were examined. Additionally, it washypothesized that data gathered from an actual bout rather than a discrete laboratory trial would yield different results. METHODS The design of the study was an observational case study with all data collection taking place in a U.S. fencing club. The participant was an internationally top ranked Russian saber fencer. Kinematic data were collected and analyzed using the Peak 2D videography equipment operating at 120 Hz and its accompanying software package. Six lunge attacks and the preceding movement were digitized from the fencing bout. Variables investigated included: displacement of the forward heel, displacement of the hip, hip velocity, trunk angle, and hip and knee acceleration. RESULTS The length of the lunge attack (as measured by displacement of the heel) averaged 1.24 m with a range of '884 m to 1.86 m. The average amount of total vertical oscillation of the hip in the movement preceding thelunge was .034 m and the average change in vertical displacement as the fencer lunged was .I38 m. The average velocity of the fencer (as measured by the velocity of the hip marker) was 1.97 m/s with a range of 1.38 m/s to 2.22 mls. The average position of the trunk during the fencing movement and the lunge was a forward tilt of 17.46 degrees and the average amount of motion of the trunk during the footwork sequence was 7.48 degrees. The average peak acceleration for the hipand knee was 8.57 m/s/s and 21.65 m/s/s, respectively. The peak acceleration of the hip occurred at the end of the lunge while the peak acceleration of the knee occurred mostly during mid lunge. Furthermore, minimum acceleration of the hip occurred during mid lunge. DISCUSSION AND CONCLUSION Control of balance (minimum vertical oscillation and trunk sway) may contribute to the abilities of an elite level fencer. Additionally, being able to accelerate quickly from the pre-lunge phase to the lunge may make the fencer attack more effective (increase Likelihood of closing distance very quickly and thereby scoring a touch). Lunge length and average velocity results in this study may differ from past studies due to the difference in designs (Klinger, Adrian, & Dee, 1985; Szilagyi, 1992). Past studies have asked participants to give a maximal effort when performing discrete fencing movements based on simple visual or auditory Wes. Often times lunging as long as possible or as quickly as possible may not be advantageous as much asrecognizing and manipulating the distance from the opposing fencer. REFERENCES Klinger, A., Adrian, M., & Dee, L. (1985). Effect of pre lunge conditionson performance of elite female ' fencers. In Terauds & Barham (eds.), Biomechanics in Sports 11. Proceedings of ISBS 1965, (p. 210-215). Greeley, Colorado: ISBS. Szilagyi, T. (1992). Examination of the velocity of fencing Lunge. In Rdano, R. (Ed.), ISBS 1992 Proceedings of the loth Symposium of the International Society of Biomechanics in Sports (pp. 71-73). Milan, Italy: ISBS
CONSISTENCY IN KINEMATIC MOVEMENT PATTERNS AND PREDICTION OF BALL VELOCITY IN THE FOOTBALL PLACEKICK
Football games can be won or lost "off the foot" of a kicker. It
may be a point after touchdown (worth 1 point) or a field go 1(worth 3 points). The keys to the success of a kick depend on the strength/power of the kicker's leg and the accuracy with which he can kick the ball through the uprights
WHAT IS LEG DOMINANCE?
INTRODUCTION
Often in research studies, it is important to assess right and/or left dominance of the hand or foot. Contrary to hand dominance, minimal attention has been given to the concept of leg or foot dominance. In the simplest terms, leg dominance has been determined by which hand is dominant. If one is right-handed, then one must be right leg dominant. If one is left-handed, then one must be left leg dominant. In other instances, leg dominance has been determined by a one-or two-foot item skills test such as kicking a ball or stepping up on a chair. (Harris, 1958; Kovak and Horkvic, 1970; Peters and Durding, 1979; and Porac and Cohen, 1981). It was not until the Chapman et al. (1987) test was designed that a more comprehensive assessment was possible. They developed a test of 13 items which included both manipulative and weight bearing activities. Alrernative tests of leg dominance have been based on the strength of the two legs and how it is related to handedness. Singh (1970) studied the strength of the legs in a pushing activity and found that the right legs of right-handed subjects were no different than their left legs, but found that left-handed subjects had stronger left legs than right legs. On the other hand, Carnahan et al. (1986) and Rosenrot (1980) reported leftfoot superiority in strength of force production in right handers. It also has been implied by some that because the left leg in right-handed people is longer and heavier, it must be stronger (Chibber and Singh, 1970). This has not, however, been fully substantiated.
Friberg and Kvist (1988) studied handedness and leg length inequality in athletic jumping performances. They found no relationship between takeoff leg and handedness, but a significant relationship between leg length inequality and takeoff leg. The longer leg generally was the preferred leg. Therefore this study was undertaken to:
1) compare the contralateral strength of the quadricep and hamstring muscles in right and left leg dominant subjects; and
2) compare manipulative and weight bearing activities in right and left leg dominant subjects
KINEMATIC CHANGES AT BALL RELEASE IN BASEBALL PITCHING OVER A SIMULATED GAME OF BASEBALL
INTRODUCTION The defensive nature of baseball causes it to be dominated by the skill of the pitcher, who through speed of pitch or a combination of speed and guile in controlling the ball often determines the result of the game (Polk, 1982). Correct pitching mechanics enables a pitcher to throw the ball repeatedly at high velocities without undue risk of injury. Nowhere is this more important than in the late innings of a game. PURPOSES AND METHODS The purpose of this study was to kinematically describe and compare the changes in stride length, foot contact, ball release time, release height, ball velocity and knee, hip, and trunk angle at ball release over a simulated single game of baseball pitching in collegiate pitchers. Seven male collegiate pitchers were filmed pitching a simulated , 7inning baseball game. Each inning consisted of 14 pitches following the protocol as suggested by Potteiger, Blessing, and Wilson (1992). Every other pitch was to be thrown with 100% effort while the other pitches were to be thrown at 80% effort. The first, seventh, and thirteenth pitches of innings 1,4, and 7 were required to be fast balls and were filmed using the Peak5 2D video system. Film data were collected at 120 Hz. A Jugs radar gun was used to collect the velocity of the baseballs being pitched. A 3 x 3 analysis of variance with an alpha level set at
HORIZONTAL BAR DISPLACEMENTS OF WOMEN WEIGHTLIFTERS DURING THE SNATCH
The purpose of this study was to analyze the horizontal bar displacement of women weightlifters while performing the snatch. Thirty lifts performed at the 1999 United States National Weightlifting Championships were recorded and analyzed using a Peak5 2D Motion Analysis System. Three key displacement values were obtained for each lift: first pull, second pull, and just after peak height. The magnitude of bar displacement ranged from โ3 to 8cm, for the first pull โ14 to 14cm, for the second pull, and โ3 to 21cm just after peak height is attained. Lifters did not display the horizontal displacement pattern that is described for men in the current literature
KINEMATIC ANALYSIS OF THE BAR DROP DISPLACEMENT IN THE SNATCH
The purpose of this study was to analyze drop-under time, maximum vertical barbell displacement, vertical barbell drop and maximum vertical barbell velocity during the 1999 United States National Weightlifting Championships. The performance of ten female lifters performing 30 lifts was recorded and analyzed using a Peak5 2D Motion Analysis System. These variables were observed for lifters who successfully performed multiple lifts to determine the trends that take place as the load of the barbell increases. Average maximum vertical barbell displacement was 101.5(cm) with a SD of 7.4. Average vertical barbell drop displacement was 20.8(cm) with a SD of 5.9. Average maximum vertical velocity of the barbell was 164.8(cm/s) with a SD of 19.1. Average drop-under time was .47(s) with a SD of .09