Sports Sciences Commons^™

Line Hops And Side Hold Rotation Tests Load Both Anterior And Posterior Shoulder: A Biomechanical Study, Margie K. Olds, Nicole Lemaster, Kelsey Picha, Cody Walker, Nicholas R. Heebner, Timothy L. Uhl

Sports Medicine Research Institute Faculty Publications

Background: Clinical tests should replicate the stressful positions encountered during sport participation. Evaluating the kinetic and electromyographical demands of clinical tests enables clinicians to choose appropriate tests for specific sports.

Purpose: To describe the shoulder forces and muscle activation levels during closed chain functional tests of Line Hops (LH) and Side Hold Rotation (SHR).

Study Design: Descriptive biomechanical study.

Methods: Ten asymptomatic participants were examined in a university laboratory. Two functional tests were evaluated using three-dimensional video analysis and electromyography to measure shoulder forces, moments, and muscular activity levels.

Results: SHR produced a peak average posterior translation force of 4.84 …

Examination Of Sex- And Intensity-Specific Fatigue During Bilateral Leg Extension Exercise, Taylor Kayln Dinyer

Theses and Dissertations--Kinesiology and Health Promotion

The purposes of this study were to: 1) examine sex-related differences in the performance of repetitions to failure below (CL_-10%, CL_-20%) and above (50%, 60%, 70%, and 80% 1RM) the critical load (CL) to make inferences regarding the mechanisms responsible for variability in the performance of repetitions to failure at varying loads; 2) examine the time course of neuromuscular and muscle oxygen saturation responses during the performance of repetitions to failure below and above the CL; 3) to make inferences regarding motor unit activation strategies used to maintain force during the completion of repetitions below and …

Effects Of Relative Inertial Load On Performance Measures And Quadriceps Electromyography During Flywheel Resistance Training Squats, Jason Todd Brantley Jr.

Theses and Dissertations--Kinesiology and Health Promotion

Flywheel resistance training (FRT) has become an increasingly popular modality for exercising due to its unique application of providing external resistance. Little is known about how changes in relative inertial loads affects performance and electromyography (EMG) activity. The purpose of this study was to examine how performance metrics and quadriceps EMG activity are affected by relative inertial load during FRT-based squats. Fifteen resistance trained individuals completed five sets of five repetitions of squats with varying relative inertial loads in random order. Peak Eccentric Power (PEP), Peak Concentric Power (PCP), average force, total work, and repetition time were measured. Surface level …

Static Stretching And Preconditioning Exercise Augments Power Output In Recreational Athletes, Mark R. Mason

Theses and Dissertations--Kinesiology and Health Promotion

The purpose of this study was to determine the independent and combined effects of performing a preconditioning exercise and antagonist stretching on vertical jump (VJ) performance. Twenty club rugby players performed a VJ in four conditions: control condition, following static stretching, following a preconditioning exercise, and following the combined treatment of static stretching and a preconditioning exercise. Electromyographic (EMG) activity was measured in the gluteus maximus, vastus lateralis, gastrocnemius medialis, and tibialis anterior during the VJ trials. Repeated measures ANOVA were used to compare VJ and EMG outcomes across conditions. A Bonferroni correction was used to account for multiple post-hoc …

The Effect Of Tactical Tasks And Gear On Muscle Activation Of Swat Officers, Jason M. Keeler

Theses and Dissertations--Kinesiology and Health Promotion

Special Weapons and Tactics (SWAT) officers constitute a subgroup of specialized law enforcement officers that perform a variety of tactical operations while wearing approximately 40 kg of tactical gear. Lower back pain is a prevalent musculoskeletal injury suffered by SWAT officers. Tactical gear places significant stress on the lower back. Thus, it is important to quantify the effect that tactical gear has on muscle activation levels of torso musculature while performing occupational tasks. Electromyography was evaluated on 20 male subjects (age: 34.7±4.5 yr.; height: 1.79±.10 m; body mass: 91.53±17.32 kg; mass of gear: 13.82±1.90 kg) while performing four tactical tasks …