Biomechanics Commons^™

The Effect Of Load On The Kinetics And Kinematics Of The Lower Extremity During Landing, Michael Akira Sullivan

Theses and Dissertations

Purpose: To understand the differences in the lower extremity kinetics and kinematics as load increases during jump landings. Methods: Ten male participants (20.4 years ± 2.41 years, 108.8kg ± 14.02kg) took part in two testing sessions. The first testing session involved testing each participant’s 1-repetition max in the hexagonal barbell deadlift. The second testing session involved the data collection of the jumping trials for each participant. Participants performed their countermovement jumps under seven randomized conditions. Six of the conditions involved the hex bar using loads equivalent to 10, 20, 30, 40, 50, and 60% estimated 1-repetition max of the hexagonal …

Modeling Individual Muscle Forces In The Lower Extremity During Loaded And Unloaded Hexbar Vertical Jumps, Abigail Salvadore

Theses and Dissertations

Hexagonal barbell (HB) loaded jumps are often used in training to increase lower extremity power. Given the importance of coordinated muscular effort in achieving maximal power output, an understanding of how the lower extremity musculature individually performs during loaded jumps would be advantageous. The purpose of this study is to describe the effect of load on individual muscle forces, muscle torques, and the contribution to the net joint moment (NJM) during the concentric phase of loaded HB jumps.10 male collegiate athletes performed 5 maximal HB jumps at 0%, 20%, 40% and 60% of their HB deadlift 1-repetition maximum. Filtered Ground …

A Full Collegiate Volleyball Season Does Not Influence Jumping Or Landing Performance In Freshmen And Sophomore Players, Christian Noel Sanchez

Open Access Theses & Dissertations

Knee injuries are devastating and typically experienced by athletes when performing jumping and landing tasks throughout a complete collegiate volleyball season. The purpose of this study was to examine changes in lower extremity strength, frontal plane knee angles and moments, jump performance during a countermovement and approach jump before and after a complete Division I collegiate volleyball season in female volleyball freshman and sophomores. Eight freshman/sophomore female collegiate volleyball players participated in the study. Lower extremity strength was assessed using an isokinetic dynamometer, kinematic and kinetic data were obtained through three-dimensional motion capture system and force platforms, respectively. Participants performed …

Biomechanical Analysis Of Jumping: The Influence Of External Load And Countermovement Depth On Deceleration Strategies And Performance, Leland Adam Barker

UNLV Theses, Dissertations, Professional Papers, and Capstones

Jumping performance has traditionally been measured by jump height alone. In recent years, the reactive strength index (RSI = Jump height / jump time)) has been used as another measure of jump performance. According to RSI, which was developed to assess eccentric force production, jump performance can improve by increasing jump height, decreasing jump time, or both simultaneously. However, it is not clear how force production correlates to RSI variables. If RSI is meant to be a practical measure of eccentric force production, it should correlate strongly to eccentric and amortization force production during jumping. Thus, the purpose of the …

Effect Of Warm-Up Activity On Vertical Ground Reaction Forces In Basketball Players During Drop Jump Landings, Jacob Wesley Hinkel-Lipsker

Master's Theses

ABSTRACT

Effect of Warm-Up Activity on Vertical Ground Reaction Forces in Basketball Players During Drop Jump Landings

Jacob Hinkel-Lipsker

Purpose: The purpose of this study was to examine the effect of certain warm-up activities on vertical ground reaction forces (GRF_v) during a drop jump landing. Methods: Eight women and twelve men (mean age 22.6 ± 1.82 years) completed three warm-up activities on three separate days in a counterbalanced order: a passive stretching warm-up, a dynamic warm-up, and a no warm-up control. After completing each activity, participants were asked to perform eight drop jump landings on a force platform. …

The Effects Of Two Different Fatigue Protocols On Lower Extremity Kinematics And Kinetics During An Unanticipated Running Stop-Jump, David L. Quammen

Human Movement Studies & Special Education Theses & Dissertations

Altered neuromuscular control strategies and biomechanical movement risk factors are most likely to contribute to the increased incidence of non-contact ACL injury for female athletes. Neuromuscular control strategies and movement patterns are further altered when the effects of fatigue are present. The purpose of this study was to determine neuromechanical differences between two fatigue protocols [Slow Linear Oxidative Fatigue Protocol (SLO-FP) and Functional Agility Short-Term Fatigue Protocol (FASTFP)] when performing a running stop-jump task (RS). A sample of convenience of fifteen Division I female soccer players (age= 19.2 ± 0.8 years; height= 1.67 ± 0.05 m; mass= 61.7 ± 8.1 …

The Effect Of Instruction On Jump-Landing Kinematics In Collegiate Age Female Athletes Over Time, Jena Lynne Etnoyer

Human Movement Studies & Special Education Theses & Dissertations

The use of verbal and video instruction is a simple feedback tool that can be implemented into almost all clinical rehabilitative and prevention programs. The purpose of this study was to determine whether self or a combination of self and expert feedback will have a long term effect on box-drop jump (BDJ), running-stop jump (RS), and sidestep maneuver (SS) lower extremity kinematics (knee flexion, knee valgus, hip flexion, hip abduction) over time in healthy college age female athletes. A repeated measures design was used. Forty-three physically active females (age=21.47±1.55years; height=l.65±0.08m; weight=63.78±12kg) were randomly assigned to three groups; 15 self feedback(S), …