Award Date

5-1-2021

Degree Type

Dissertation

Degree Name

Doctor of Philosophy (PhD)

Department

Kinesiology and Nutrition Sciences

First Committee Member

John Mercer

Second Committee Member

James Navalta

Third Committee Member

Steen Madsen

Fourth Committee Member

Nancy Lough

Number of Pages

80

Abstract

The purpose of this dissertation is to investigate the relationship between jump performance and asymmetry. This investigation was divided into three separate studies. The first aim investigated which asymmetry variables for eccentric and concentric phases best predicted jump height (JH) during different jump types. The aim of the second study was to determine if asymmetry variables differed between jump type and genders.

Fourteen participants performed countermovement jumps (CMJ) and drop vertical jumps (DVJ). The DVJ were administered from a 30.5 cm platform leading with dominant leg striking separate force platforms with each foot. Vertical ground reaction forces were used to determine eccentric and concentric phases. Variables identified for each leg during both phases were: average force, rate of force development, velocity, power and impulse. Asymmetry for each variable was calculated using the formula: (DL – NDL) / (DL + NDL)*100. Flight time was derived from ground contact during landing phase subtracted from takeoff during propulsion phase.

The third study investigated if asymmetry variable differed between CMJ with and overhead goal (OG) or no overhead goal (NOG). Sixteen participants performed maximal effort CMJ with OG and NOG. Data processing and identifying of variables followed same methods as first two studies.

The first aim used a linear stepwise regression and determined only impulse asymmetry during the concentric phase for CMJ (F(1,12) = 44.564, p.001, R2 = 0.788), and for DVJ only eccentric peak force and concentric RFD were selected as predictors of JH (F(2,11) = 23.962, p< 0.001, R2 = 0.813). The second aim used a 2 (jump type) x 2 (gender) mixed factor ANOVA and determined only peak concentric GRF asymmetry (F(1,12) = 6.442, p>0.026) and average iv concentric GRF asymmetry (F(1,12) = 5.145, p>0.043) had an interaction between gender and jump type ( >0.05). The third aim used a dependent t-test and determined that JH (t(15) = -2.565, p

Keywords

Asymmetry; Countermovement Jump; Differences; Drop Vertical Jump; Force; Relationship

Disciplines

Biomechanics

File Format

pdf

File Size

1303 KB

Degree Grantor

University of Nevada, Las Vegas

Language

English

Rights

IN COPYRIGHT. For more information about this rights statement, please visit http://rightsstatements.org/vocab/InC/1.0/


Included in

Biomechanics Commons

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