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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

A kinematic analysis of the role of the upper-extremities during vertical jumping

Connell, Robert January 2013 (has links)
Over the last two decades, plyometric training has been extensively adopted by athletes, coaches and sport scientists with a primary aim to improve vertical jump height. The focus of these plyometric programmes has been to train the lower-extremity musculature in order to enhance jump performance. However, the lower-extremities are not the only contributing factor to vertical jump performance, as the use of an arm-swing during vertical jumping has also been shown to contribute to achieving maximum vertical jump height, yet training programmes for improving the arm-swing during the vertical jump are limited. Therefore, the primary aim of this thesis was to examine the full arm-swing mechanics during vertical jumping, and to then develop and assess the suitability of an upper-extremity plyometric programme for increasing both arm-swing kinematics and jump height. Firstly, a descriptive study was conducted to assess if an arm-swing countermovement was utilised during the vertical jump, which was deemed the prerequisite for using plyometric training to improve the arm-swing. Then an experimental study was conducted comparing vertical jumps performed with and without an arm-swing countermovement. The results showed that jumps performed with an arm-swing countermovement significantly increased mean peak shoulder angular velocity (ω) (+67.5 deg·s-1) and mean jump height (+ 6.2 cm) when compared to jumps performed using no arm-swing countermovement. During the final chapter of this thesis, a group of elite basketball players volunteered to participate in upper-extremity plyometric training aimed at increasing vertical jump height by training only the upper-extremities. Vertical jump height and full body kinematics were analysed using a 3 dimensional (3D) motion capture system, and key kinematic jump variables and various arm-swing performance measurements were collated both before and after a 4 week upper-extremity plyometric intervention. The use of upper-extremity plyometric training significantly increased the mean jump height (+ 7.2 cm), mean peak shoulder ω (+ 167.1 deg·s-1), mean peak frontal shoulder ω (+ 121 deg·s-1) and mean active range of motion at the shoulder joint (+ 5.3°), when compared to a control group. Furthermore, the use of a large active range of motion armswing during the arm-swing countermovement was shown to be the preferred arm-swing condition for increasing arm-swing kinematics. The increase in arm-swing kinematics and jump height after the 4 week upper-extremity plyometric programme was attributed to the participants’ improved ability to use the stretch-shortening cycle, elastic energy transfer system and stretch reflex system. Therefore, the use of upper-extremity plyometric exercises as part of a training regime for improving vertical jump performance should be advocated.
12

The moderating effect of tibialis anterior fatigue protocol on the relationships between rearfoot eversion, thigh muscle activation, and knee internal rotation during a single leg forward jump stop task

Shimokochi, Yohei January 1900 (has links) (PDF)
Thesis (Ph. D.)--University of North Carolina at Greensboro, 2006. / Title from PDF title page screen. Advisor: Sandra Shultz; submitted to the School of Health and Human Performance. Includes bibliographical references (p. 104-113).
13

Comparing the effects of different whole-body vibration intensities on vertical jump performance

Bazett-Jones, David M. 03 June 2011 (has links)
Whole-body vibration (WBV) has been shown to enhance vertical jump performance. The purpose of this study was to determine which WBV intensity has the greatest effect on counter movement jump (CMJ) height and the duration of that affect. Forty-four participants, of varying training statuses, were tested. They participated in > 4 familiarization sessions, to eliminate learning effects. Participants performed a pre-test, followed randomly by one of 5 WBV intensities. Participants performed 3 maximal CMJs immediately, 5, and 10 min following treatment. The best performance was used and calculated as a percentage of the pre-treatment values. A multivariate model (treatment X time X gender) was used to analyze the data. The three-way interaction approached significance (p=0.053) and significance was found for all two way interactions. Females performed the best immediately following the 2.71g treatment (116.9 + 38.4%). Male participants did not increase their performance; however, they may require longer durations of vibration exposure to elicit effects. The differences between males and females may also indicate that the effects of WBV are dependent on strength, stiffness, and/or training levels. Future research should continue to systematically investigate the effects of vibration and participant characteristics on WBV and performance.Keywords: power, frequency, amplitude, training, potentiation, stiffness. / School of Physical Education, Sport, and Exercise Science
14

Systematic study of the genus Craspedolepta Enderlein, 1921 (Homoptera: Psyllidae) in North America.

Joumet, Alan R. P. January 1973 (has links)
No description available.
15

A dynamical systems investigation of loaded jump squat kinematics

Kruger, Sarah E. January 2005 (has links)
The purpose of this project was to assess the coordination and performance of the jump squat movement for multiple loading conditions. Seventeen male subjects between 18 and 30 years of age, performed two jump squats for each loading condition, 0-60% of their one repetition maximum (1 RM) incremented by 10% for each trial. Video capture was used to assess kinematics and a force platform in combination with a linear position transducer was used to determine power. All of the peak power values occurred between 0% and 30% of 1 RM and there was an overall linear decrease in power output from 0-60% (p = 0.000). The shank-thigh and thigh-trunk mean absolute relative phase (MARP) values were shown to have linear increases from 0-60%, with p-values of 0.003 and 0.014 respectively. The MARP values calculated from 0-30% were significantly different than those at 60% for both segmental relationships. These results indicate that optimal jump squat performance occurs from 0-30% of 1 RM. / School of Physical Education, Sport, and Exercise Science
16

Methods for determining power output and factors affecting the optimal load during free-standing jump squats

Newell, Philip B. January 2005 (has links)
The purpose of this thesis was to determine the validity of an linear position transducer / force platform method as compared to a 2D video analysis / force platform method for determining power output during free-standing jump squats, and to examine the effects of strength level and sport background on the optimal load for power output. The results showed that the LPT method was not suitable for measuring power output during free-standing jump squats. In addition, the optimal load range was determined for the VA method to occur between 10% and 20% of a predicted 1RM squat. Strength level did not have a significant affect on the optimal load, however, there were differences in strength and power output by sport. It is recommended that future research examine the specific limitations of an LPT for measuring un-constrained movements, as well as the effects of athletic and training background on the optimal load. / School of Physical Education, Sport, and Exercise Science
17

Time to stabilization : number of practice trials and measured trials needed /

VanMeter, Ashley. January 2007 (has links)
Thesis (M.S.E.S.)--University of Toledo, 2007. / Typescript. "Submitted as partial fulfillment of the requirements for The Master of Science degree in Exercise Science." Bibliography: leaves 38-39.
18

The effect of wearing strength shoes during plyometric training on vertical jump performance /

Jenkins, Karen M., January 1993 (has links)
Thesis (M.S. Ed.)--Virginia Polytechnic Institute and State University, 1993. / Vita. Abstract. Includes bibliographical references (leaves 55-58). Also available via the Internet.
19

Differences in lateral drop-jumps from an unknown height among individuals with ankle instability

Rosen, Adam B. January 2008 (has links)
Thesis (M.S.)--University of Delaware, 2008. / Principal faculty advisor: Charles B. Swanik, Dept. of Health, Nutrition, & Exercise Sciences. Includes bibliographical references.
20

An examination of lower extremity sex differences in continuous relative phase during a drop jump and two different unplanned cutting maneuvers

Galobardes i Tuneu, Arnau. January 2007 (has links)
Thesis (M.S.)--Plymouth State University, 2007. / Includes bibliographical references (leaves 281-306).

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