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James G. Hay and Timothy J. Koh

The purpose of this study was to develop measures of a long or triple jumper’s ability to use programming and visual control strategies during the approach to the takeoff. Five such measures were developed. The performances of the competitors in the men’s and women’s horizontal jumps at the 1987 Big Ten Conference Championships were filmed to obtain the required data. Percentiles were computed for each of the five measures and these were used, in conjunction with a performance profile, to evaluate the ability of an athlete to use the two strategies.

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Timothy J. Koh and James G. Hay

The motions of the landing leg in the final three strides of the approach in the long jump are described, as are the relationships of these landing leg motions with performance. Film analysis of 19 elite male long jumpers competing in the 1986 and 1987 TAG (U.S. national) Championships showed that backward sweeping, or “active,” landings were used in each stride considered. However, the landing in the last stride was less active than those in the two preceding strides. A mathematical model showed that muscle action reduced the forward horizontal velocity of the landing foot in each landing. There were no statistically significant correlations of measures of landing leg motion with measures of performance. However, there was some indication that landing leg motion plays a role in lowering the center of gravity in the second-last stride and that this lowering increases the distance of the jump. There was also some indication that placing the landing foot well forward of the body at the end of the last stride benefits the distance of the jump, perhaps by promoting the development of vertical velocity during the support phase of the jump. This appears to be more important than minimizing the loss in horizontal velocity during the support phase of the jump.

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Timothy J. Koh and James G. Hay

The motions of the landing leg preceding the support phases of the hop, step, and jump, thought to be important in the triple jump, are described. Film analysis of 16 elite male triple jumpers competing in the 1986 and 1987 TAC (U.S. national) Championships showed that backward sweeping, or “active,” landings were used prior to each support phase. A mathematical model showed that muscle action reduced the forward horizontal velocity of the landing foot during each landing. There were no statistically significant correlations of measures of landing leg motion with measures of performance. The landing prior to the jump phase was less active than the two preceding landings. However, the elite athletes in the present study were much more active in this landing than athletes of lesser ability. There was also some indication among the subjects of this study that activeness in this landing was associated with long triple jumps. Thus, activeness in this landing appears to be desirable but very difficult to achieve and/or use effectively.

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Gregory C. Bogdanis, Athanasios Tsoukos, and Panagiotis Veligekas

Purpose:

To examine the acute effects of a conditioning plyometric exercise on long-jump performance during a simulated long-jump competition.

Methods:

Eight national-level track and field decathletes performed 6 long-jump attempts with a full approach run separated by 10-min recoveries. In the experimental condition subjects performed 3 rebound vertical jumps with maximal effort 3 min before the last 5 attempts, while the 1st attempt served as baseline. In the control condition the participants performed 6 long jumps without executing the conditioning exercise.

Results:

Compared with baseline, long-jump performance progressively increased only in the experimental condition, from 3.0%, or 17.5 cm, in the 3rd attempt (P = .046, d = 0.56), to 4.8%, or 28.2 cm, in the 6th attempt (P = .0001, d = 0.84). The improvement in long-jump performance was due to a gradual increase in vertical takeoff velocity from the 3rd (by 8.7%, P = .0001, d = 1.82) to the 6th jump (by 17.7%, P = .0001, d = 4.38). Horizontal-approach velocity, takeoff duration, and horizontal velocity at takeoff were similar at all long-jump attempts in both conditions (P = .80, P = .36, and P = .15, respectively).

Conclusions:

Long-jump performance progressively improved during a simulated competition when a plyometric conditioning exercise was executed 3 min before each attempt. This improvement was due to a progressive increase in vertical velocity of takeoff, while there was no effect on the horizontal velocity.

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William P. Berg and Nancy L. Greer

This study determined the kinematics of the final 11 steps of the long jump approach (LJA) for 19 novice long jumpers. Associations between takeoff accuracy and jump performance were identified, and comparisons of LJA kinematics were made with previous investigations of horizontal jumps performed by expert long jumpers. Results indicated that absolute takeoff error was not an important determinant of jump distance for the novice long jumpers. Additionally, novice jumpers differed from expert jumpers in terms of the relationships among specific variables. The results suggest that kinematic variables that appear to be causally related to jump performance in experts may not piay a similar role in the performance of novices. Hypotheses for these differences were offered. Differences between the LJAs of novice and expert long jumpers warrant further investigation, so that their origins can be determined and used to develop effective training regimes.

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John A. Miller Jr and James G. Hay

The horizontal jumps at the 1985 TAC (U.S. national) Championships in Indianapolis were filmed as part of the Elite Athlete Project of the U.S. Olympic Committee. Jumps by Willie Banks and Mike Conley were especially outstanding and, because of this as well as some excellent performances by the third and fourth place finishers, an analysis of the jumping techniques used by the top four finishers was conducted. Its purposes were (a) to determine selected kinematic data for a world record triple jump, and (b) to compare these data with corresponding data for previous performances by the same athlete and for performances by other elite triple jumpers. A comparison of the phase distances and phase ratios for the 1985 TAC jumps with those for the best analyzed jump by Banks, Conley, and Joyner at some previous meets revealed that, as they increased their effective distances, all three decreased the emphasis they placed on the step phase. The best athletes seem to use a “pawing” (or active) landing prior to takeoff into the step phase and a “blocking” landing prior to takeoff into the jump phase.

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Christopher D. Ramos, Melvin Ramey, Rand R. Wilcox, and Jill L. McNitt-Gray

This study investigates the effect of initial leg angle on horizontal jump performance. Eleven highly skilled male and female long jumpers (national and Olympic level) performed a series of horizontal jumps for distance. Within-jumper differences in initial leg angle, normalized horizontal and net vertical impulses, contact time, and average reaction force during the impact interval, postimpact interval, and in total were measured using high-speed video (240 or 300 Hz) and a force plate (1200 Hz). Pearson’s correlations, Winsorized correlations, and the HC4 method were used to determine significant correlations between variables (α = .05). Within-jumper analysis indicated that when jumpers initiate the takeoff phase with a larger leg angle they are able to generate significantly greater negative horizontal and positive net vertical impulses (n = 7). Increased impulse generation was the result of increased contact time (n = 5 of 7) and/or increased average reaction force (n = 4) during the impact interval (n = 3) and/or postimpact interval (n = 4), depending on the individual. Initial leg configuration at contact and individual specific impulse generation strategies are important to consider when determining how an athlete with initial momentum can increase impulse generation to jump for distance.

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Borja Muniz-Pardos, Alejandro Gómez-Bruton, Ángel Matute-Llorente, Alex González-Agüero, Alba Gómez-Cabello, José A. Casajús, and Germán Vicente-Rodríguez

Purpose: To examine the effects of a 6-month whole-body vibration (WBV) training on lower-body strength (LBS), lower-body power (LBP), and swimming performance in adolescent trained swimmers. Methods: Thirty-seven swimmers (23 males and 14 females; 14.8 [1.3] y) were randomly assigned to the WBV (n = 20) or the control group (n = 17). Isometric LBS (knee extension and half squat) and LBP (vertical and horizontal jumps and 30-m sprint) tests were performed before and after the intervention period. Swimming performance times in 100 m were collected from official competitions. As time × sex interaction was not found for any variable (P > .05), males and females were analyzed as a whole. Results: Within-group analyses showed a most likely beneficial moderate effect of WBV on isometric knee extension (effect size [ES] = 0.63), 30-m sprint test (ES = 0.62), and 100-m performance (ES = 0.25), although these were corresponded with comparable small to moderate effects in the control group (ES = 0.73, 0.71, and 0.20, respectively). The control group obtained a small possibly beneficial effect of swimming-only training on vertical jump performance, whereas no effect was observed in the WBV group. Unclear effects were observed for the rest of the variables assessed. Between-group analyses revealed unclear effects of WBV training when compared with the control condition in all studied variables. Conclusions: There is no current evidence to support the use of WBV training, and therefore, coaches and sports specialists should select other methods of training when the aim is to increase LBS, LBP, or swimming performance.

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Jessica A. Calderbank, Paul Comfort, and John J. McMahon

phase of the jump (ie, when the force platform was unloaded). 21 Horizontal Jumps Testing for the broad jumps (CMBJ and TSBJ) took place on a flat sports hall floor. Jump distance was recorded to the nearest centimeter using a measuring tape. For CMBJs, participants were instructed to start with the

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Rodrigo Ramirez-Campillo, Cristian Alvarez, Felipe García-Pinillos, Paulo Gentil, Jason Moran, Lucas A. Pereira, and Irineu Loturco

horizontal jumps) in soccer players ( 21 ). Similar to the ES norms previously described, to evaluate the TEC, a magnitude-based inference approach is applied, using the ratio between the result gain (ES) in the analyzed physical qualities [eg, CMJ, MB5, COD, 5RM, 2400-m TT, and MKD; also considered as the