Medicine and Health Sciences Commons^™

Backpack Load And Unload Influence On Positional Parameters In The Static Posture Of College Students, Katya Mata, Hevan Nieto, Bryon C. Applequist, Breanna Morales

International Journal of Exercise Science: Conference Proceedings

The investigation into the load carrying of military applications and children with a disability has been thoroughly evaluated. A population that has been largely ignored, though they are subjected to load carrying daily is the college student. College students often carry books and notebooks from class to class and can be subjected to substantial loads. PURPOSE: The purpose of this study was to investigate the effects of backpack load on positional parameters of static posture in college students. METHODS: Nineteen college-aged students (n = 19, Age = 21.4 ± 1.3 years, Height = 1.7 ± .1 m, Weight = 66.7 …

Seasonal Shifts In Jumping Patterns: A Study Of Countermovement Jump Strategies In High School Football Athletes, Alexa L. Lobato, Samuel T. Lauman, Lindsey C. Hartland, Lucy H. Phan, John P. Abt

International Journal of Exercise Science: Conference Proceedings

Modern sporting trends have begun to adopt sport science and load monitoring to identify in-season trends with the goal of improving performance and reducing injury. Although these resources have become increasingly common in professional and collegiate sports, many high school athletic programs have yet to adopt such technologies. While previous research has demonstrated season-long changes in jump performance, no research has investigated the impact of in-season demands on the changes in jump strategy in male high school football athletes. PURPOSE: The purpose of this study was to examine changes in jump strategy in high school football players over a …

Countermovement Jump Performance Trends In High School Football Players Throughout A Competitive Season, Samuel T. Lauman, Alexa L. Lobato, Lindsey C. Hartland, Lucy H. Phan, John P. Abt

International Journal of Exercise Science: Conference Proceedings

Football is the largest participation sport amongst male high school athletes in the country with over one million participants. Previous research has demonstrated that countermovement jump (CMJ) performance is negatively affected by in-season fatigue in contact sports such as rugby and hockey. However, little data are available to describe how CMJ performance and force metrics change in high school athletes throughout a competitive football season. PURPOSE: The purpose of this study was to examine the changes in strength and power metrics in high school football players over a single football season. METHODS: Sixty-nine male high school football athletes …

The Effect Of Vision On Isokinetic Muscular Power, Mika Weaver, Casi Helbig, Patrick Cereceres

International Journal of Exercise Science: Conference Proceedings

Isokinetic muscular power is the ability to generate force at a constant speed. PURPOSE: The purpose of this study was to determine the effect of vision on isokinetic muscular power. METHODS: Participants in this study consisted of twenty-four students from Texas Lutheran University (18 male and 6 female). The mean age was 18.8 with a standard deviation of 1.18. The mean height was 68.67 inches with a standard deviation of 4.26. The mean weight was 177.65 lbs with a standard deviation of 41.06. Subjects met at the Kieffer Kinesiology Laboratory to perform two tests on two different days. …

Human Electrical Brain Dynamics During Locomotor Obstacle Avoidance In Virtual Reality, Carter L. Hartman, Yu-Po Cheng, Andrew Nordin

International Journal of Exercise Science: Conference Proceedings

Visually identifying and avoiding obstacles encountered during walking is crucial for navigating real world environments. Motor deficits that affect gait and balance, and changes due to aging, can increase fall risk. There is a needed to better understand the complex relationships between gaze behaviors of the eye and electrical brain dynamics during locomotor obstacle avoidance. Virtual reality provides nearly limitless opportunities to create experimentally controlled, complex, realistic environments to study human behaviors, such as locomotion. PURPOSE: Our aim was to identify human electrocortical dynamics during walking and obstacle avoidance in virtual reality, to better understand visually guided human locomotor …

Measures Of Center Of Pressure And Lower Leg Muscle Electromyography During Landing Before And After Plantar Flexor Stretch, Connor Hill, Brittany Coltrain, Michael Olson

International Journal of Exercise Science: Conference Proceedings

Static stretching of the plantar flexor muscles is reported to modify neuromuscular responses to external stimuli. However, it is not known how these muscles respond to external loading in an applied task, such as single-leg drops. Further, if mechanical laxity in the plantar flexor muscles is present after stretching of it is unclear how this laxity will influence the muscle activation and movement patterns of the lower extremities. PURPOSE: This study is intended to further explore the response of the lower extremities to plantar flexor muscle stretch in an effort to understand its impact on potential injury. METHODS: …

Modified Torque Output And Lower Leg Muscle Electromyography After Passive Stretching, Brittany Coltrain, Connor Hill, Michael W. Olson

International Journal of Exercise Science: Conference Proceedings

Increased stretch of the plantar flexor muscles is reported to increase tissue laxity of the tendons and reduces force output, but in other studies the tendon biomechanical properties are not affected and force output is not changed after stretch. PURPOSE: To examine the force output and muscle electromyography activity of lower leg muscles to a prolonged passive stretch. METHODS: Five participants (20.6 ± 1.1 yrs: 1.78 ± 0.1 m:, 80.6 ± 9.9 kg) performed maximal plantar and dorsi flexion isometrically while secured to an isokinetic dynamometer. They were seated upright with ~90 deg hip flexion. The knee was …

Biomechanical Assessment Of Footwear And Foot Landing Types In Collegiate Female Runners At Preferred Running Speed, Shivaniba Gohil, Michael W. Olson

International Journal of Exercise Science: Conference Proceedings

Barefoot and shod running with conditions at heel landing and forefoot landing has implications on running biomechanics. PURPOSE: To investigate the impact of two footwear and two foot landing type conditions on lower limb and lumbar acceleration and kinematics. METHODS: Six collegiate female runners (20.6 ± 1.5 yrs, 58.6 ± 4.7 kg, 1.63 ± 0.05 m) performed running trials on a motorized treadmill. Their averaging running volume was 49.6 ± 31.5 km/wk (range: 16.1 – 80.5 km/wk). Inertial measuring units (IMUs) (370 Hz), containing triaxial accelerometers (1g = 9.81 m/s/s) and gyroscopes (deg/s), were secured on the foot/shoe …

Comparison Of Overground, Motorized Treadmill And Non-Motorized Treadmill Gait, Kevan D. Kennedy, Scott P. Mclean, Emma Williams

International Journal of Exercise Science: Conference Proceedings

Shaulis et al., (2022) found that walking on a non-motorized treadmill (NMT) elicited greater EMG activity from plantar flexor (PF) muscles compared to walking overground (OG) and on a motorized treadmill (MT). PURPOSE: To compare kinematics, kinetics and EMG in OG, MT, and NMT walking. METHODS: Twenty-one healthy adults (24.4±7.2 yrs, 1.75±0.09 m, 75.4±13.1 kg) completed one trial of walking at 3.0 mph in each of three modes (OG, MT, NMT). All dependent measures were averaged across a minimum of two consecutive gait cycles. Surface EMG of the Gastrocnemius (GA), and Tibialis Anterior (TA) was collected at 1000 …

The Influence Of Initial Foot Position During Stand To Sit On Trunk And Knee Joint Movement Control, William V. Erlandson, Linda Steele

International Journal of Exercise Science: Conference Proceedings

During StandTS, trunk flexion and knee extensor eccentric control are two key factors influencing descending balance control of StandTS movement- trunk flexion plays an important role in controlling the vertical downward acceleration of the center of mass, while knee extensor eccentric control is essential for arresting the falling momentum to ensure a stable and safe landing. Since the initial foot position (IFP) is an important factor that can improve sit-to-stand (STS) performance by modifying STS kinematics and kinetics during the uprising phase, we explored the effects of IFPs on StandTS. PURPOSE: The purpose of this study was to examine the …

The Relationship Between Shoulder Mobility And Upper Body Muscle Mass On 2-Rm Bench Press Performance, Raquel J. Cavazos, Francesca Aquilino, Ernesto Balderrama, Chaehyun Byun, Shelby Gerner, Cheyenne Martinez, Austin Riffe, Vipa Bernhardt, Michael D. Oldham

International Journal of Exercise Science: Conference Proceedings

INTRODUCTION: Upper body strength is one of the most important factors in American football and thus tested frequently. However, strength may come at the cost of mobility as recent studies have reported an inverse relationship between shoulder range of motion (ROM) and strength, with an increase in strength causing a decrease in ROM (Shitara et al., 2022). PURPOSE: The purpose of this study was to determine if upper body muscle mass or shoulder mobility are associated with two-repetition max (2-RM) bench press performance in collegiate football players. METHODS: Data from 80 Division I varsity football players (20.5 ± 1.4 …

Intermuscular Emg Coherence Between Shoulder Muscles During Fatigue In Older Adults With And Without Rotator Cuff Disease, Xinyu Li, Huiying Zhu, Lisa Griffin

International Journal of Exercise Science: Conference Proceedings

The risk of degenerative rotator cuff disease (RCD) increases with age, partly due to changes in neuromuscular control, especially during fatiguing contractions. Intermuscular electromyographic (EMG) coherence, reflecting shared neural inputs between motor neuron pools, is essential for maintaining shoulder joint stability. PURPOSE: To determine differences in EMG coherence within the rotator cuff muscles, and between the rotator cuff and deltoid muscles, during sustained isometric fatiguing contractions in older adults with and without RCD. METHODS: Thirteen older adults with RCD (68 ± 8 yrs) and 20 without RCD (69 ± 8yrs) participated. Intramuscular EMG was recorded from the supraspinatus …

The Effects Of Liftng Belts On Power Output, Julio Aguilar, Benjamin Coldwell, Patrick Jackson, Cade Pippen, Zane Thornton

International Journal of Exercise Science: Conference Proceedings

JULIO AGUILAR, BENJAMIN COLDWELL, PATRICK JACKSON, CADE PIPPEN, ZANE THORTON.

Kinesiology & Health Science; Stephen F. Austin State University; Nacogdoches, TX

Category: Undergraduate

Advisor: Chelette, Amber, amber.chelette@sfasu.edu

Lifting belts, when lifting heavy weights, are purportedly used to support, stabilize, and attenuate the load on the spine. With the additional support, potential questions arise about whether weightlifting belts affect the power performed when squatting. This study aimed to examine the power produced during a squat with a weightlifting belt compared to a squat performed without one. Ten subjects, five male and five female, performed squats of two sets of 3 repetitions, …

Lumbopelvic Stability During A Single Leg Step Down Predicts Elbow Varus Torque During Baseball Pitching, Zachary J. Dezee, Adam J. Barrack, Kayla Bucci, Ryan J. Zerega, Rachel K. Straub, Andrew R. Karduna, Lori A. Michener

International Journal of Exercise Science: Conference Proceedings

During a baseball pitch, energy is transferred from the lower extremities through the lumbopelvic junction to produce ball velocity. Reduced lumbopelvic stability has been associated with elbow injury in pitchers, and commonly ulnar collateral ligament (UCL) tears. The primary biomechanical mechanism of UCL tears is high elbow varus torque. Understanding how decreased lumbopelvic stability influences the development of elbow varus torque could identify risk factors of UCL elbow injury. PURPOSE: Characterize the predictive ability of lumbopelvic stability on elbow varus torque during a baseball pitch. METHODS: NCAA Division 1 baseball players (N=44; 19.6+1.3yrs) participated. Pitchers threw ten fastballs from a …

Greater Motor Evoked Torque In Aclr Patients During Force Reproduction Task Compared To Health Controls, Anisha A. Patel, Christine E. Phelps, Haley Huntington, Lana J. Kayali, Caitlyn E. Olshausen, Anika Khurana, Tina Boluordi, Yong Woo An

International Journal of Exercise Science: Conference Proceedings

Persistent quadriceps dysfunction following anterior cruciate ligament reconstruction (ACLR) may lead to further pathological complication. Quadriceps weakness has been linked to corticospinal excitability. However, it remains unclear how this altered corticospinal excitability contributes to ACLR patients during knee strength tasks when compared to healthy controls. PURPOSE: The purpose of this study was to examine force reproduction strategies during isometric knee extension between ACLR patients and healthy controls. METHODS: Five ACLR (20.40±1.67yrs, 72.12±12.87kg, 171.07±7.40cm) participants and five matched healthy controls (21.00±1.73yrs, 65.77±13.61kg, 166.62±11.99cm) performed an isometric force reproduction task. They were instructed to maintain 10% of maximal voluntary isometric contraction (MVIC) …

Validation Of Vertical Force Measures During Hop Tasks Using Pressure Insoles, Andrew Cho, Erin Cagle, Sylwia Lipior, Susan Sigward

International Journal of Exercise Science: Conference Proceedings

Assessment of vertical ground reaction forces (vGRF) during jumping and landing tasks is commonly used as a tool to quantify limb loading following injury. While embedded force plates are the current gold standard, cost and poor ecological validity limit their feasibility for assessment of loading during sport agility tasks. Wearable pressure insoles can measure plantar pressure wirelessly and may provide an alternative for on-field assessments. Previous studies have assessed the validity of insoles with varying results. Few studies have considered tasks that require both vertical and horizontal forces similar to those required for agility tasks. This may have important implications …

Does Neuromuscular Fatigue Occur From One Doubles Pickleball Match?, Matthew Ritchey, Margaret Falknor, George Beckham, Eric Martin

International Journal of Exercise Science: Conference Proceedings

Pickleball is an emerging sport that is continuing to gain popularity among people of all ages. Little research has been completed on the performance aspects of the game. PURPOSE: Lower body force production is an important aspect of any sport. A countermovement jump is a useful way to test that characteristic. Acute decreases in force production are an indicator of fatigue. No previous research of force production and fatigue has been completed on pickleball. Therefore the purpose of this study was to test countermovement jump performance before and after a match of doubles pickleball to determine if neuromuscular fatigue …

Investigation Into Lower Extremity Accommodation During Lbppt Submaximal Running, Ciya Clyde, Miles Mercer, Julia Freedman Silvernail

International Journal of Exercise Science: Conference Proceedings

Running is a popular sport but often leads to overuse injuries due to repetitive ground reaction forces (GRF) impacting the lower extremities. Lower Body Positive Pressure Treadmills (LBPPT) have gained popularity in clinical and research environments for their ability to reduce the runners’ bodyweight, consequently lowering the GRFs. PURPOSE: To investigate whether there is an accommodation period present during LBPPT submaximal running for lower body GRFs. METHODS: Participants (n =3; 1 male, 2 females; age: 26 ± 1.63 years; mass: 63.73 ± 7.77kg; height: 1.64 ± 0.11m) were recruited to complete three 15-minute bodyweight support (BWS) conditions at …

Low Back Demand Of Equipment Carriage Tasks In Golf, Guanrong Cai, Jacob Cho, Yunsheng Zou, Jordan Cannon, George Salem

International Journal of Exercise Science: Conference Proceedings

Low back injury is a common concern in golfers and caddies. The literature often points to the biomechanics of the golf swing as the major contributing factor; however, golfers and caddies can regularly walk upward of 10,000 steps on uneven terrain while carrying equipment, which can contribute to the cumulative load on the low back. PURPOSE: To examine the low back biomechanical demands during golf equipment carriage and pick-up tasks. METHODS: Sixteen golfers (11M/5F, 27.4±3.5yrs) participated in 3D motion capture of a golf bag pick-up task and 3 walking tasks (1. unloaded walking [UW], 2. unilateral carrying on …

Comparing Knee Kinetics And Muscular Activity Between The Barbell Squat And Flywheel Squat In Recreationally Trained Females, Justin Lam, Janice Ko, Sean Yonemori, Jenny Nguyen, Kevin Valenzuela, Kurt A. Escobar, Joshua A. Cotter

International Journal of Exercise Science: Conference Proceedings

Previous literature has supported flywheel (FW) training with inducing muscular size and strength comparable to resistance training with free weights. However, it remains unclear how the biomechanical demands of these two training methods differ regarding reducing the risk of load-dependent injuries. PURPOSE: With the growing population of female astronauts, this study aimed to compare knee joint kinetics and muscle activation when squatting to full depth on the barbell back (BB) squat and a gravity-independent FW device utilizing technology to be deployed in future long-term space missions. METHODS: Twenty recreationally trained females (22.3 ± 2.7 yrs, 1.6 ± 0.1 m, 59.8 …

Frontal Plane Range Of Motion Differences In Unilateral And Bilateral Battle Rope Sets: A Pilot Study, Janice Ko, Sean Yonemori, Kevin Valenzuela

International Journal of Exercise Science: Conference Proceedings

Battle rope exercises are commonly used among cross-fitters to build overall muscular strength and cardiorespiratory endurance. Although this training method is physically demanding, no studies have examined the frontal plane movements in the lower extremities when performing battle ropes exercises in their different variations. PURPOSE: The objective of this research was to compare the frontal plane range of motion (ROM) along with the peak joint angles of the ankle, knee, and hip when performing bilateral and unilateral battle ropes exercises. METHODS: Participants with at least six months of resistance training experience performed four sets of bilateral and unilateral battle ropes …

The Effects Of Unilateral And Bilateral Battle Rope Exercise On The Lower Extremity Joint Force: A Pilot Study, Sean A. Yonemori, Janice Ko, Kevin Valenzuela

International Journal of Exercise Science: Conference Proceedings

The battle rope exercise recently has increased its popularity due to cross fit gyms implementing it into the workout programs. Individuals use this workout to strengthen their upper body, however it is unknown how different modalities of using the battle ropes affects the lower extremity joint force required to stabilize the body. PURPOSE: To examine the effects of unilateral and bilateral battle ropes exercises on lower extremity joint force. METHODS: Subjects performed four bilateral battle rope trials and four unilateral battle rope trials. The trials consisted of twenty seconds of continuous activity with three minutes of rest in between …

The Effects Of Fatigue On Center Of Pressure Measures During Front Lunges, Logan C. Randall, Michele Leblanc

International Journal of Exercise Science: Conference Proceedings

Front lunges are a common exercise in strength and conditioning programs. Extensive research on front lunge biomechanical movement exists previously, however, the existing research lacks information regarding fatigue or center of pressure (COP). PURPOSE: The aim of this study was to determine the effect of fatigue on COP behavior in front lunges. METHODS: Participants were ages 18 to 30 and recreationally active. Participants were guided through sufficient warm up and practiced the lunge movement, barefoot, at the cadence of 15 repetitions/minute. Step length was assigned as the length from their greater trochanter to lateral malleolus. Participants completed front lunges …

Effects Of High Heeled Gait On Knee Joint Mechanics, James Baldonado, Errin Abosolo, Harry Montoya, Zander Sadorra, Christie R. O'Hara

International Journal of Exercise Science: Conference Proceedings

Numerous women wear high heeled shoes, whether it be a professional attire, part of an outfit for a ballroom gala, or just casual day to day wear. Often, the high heel of choice in these situations is the stiletto. These shoes adversely affect natural gait and have the potential to alter joint mechanics in the knee during gait. PURPOSE: This study is designed to analyze the impacts of wearing high heels, and if it puts the user at a higher risk of a degenerative condition with repeated use. We hypothesized that all of our dependent variables would see a …

Effects Of Dance Footwear On Kinetics And Lower Limb Joint Kinematics During Sauté Jumps, Eloisa Hernandez, Erin Onat, Kevin Phan, Jenny Camacho, Ricardo Tolentino, Danielle N. Jarvis

International Journal of Exercise Science: Conference Proceedings

While some efforts have been made to design footwear that would be beneficial for dancers in terms of performance and injury prevention, most footwear commonly used by dancers offers very little support to the foot and ankle region. Footwear has the potential to modify the interaction between the foot and the floor, but there is minimal research examining the effects of footwear on dance performance. PURPOSE: The purpose of this study was to investigate the effects of footwear on ground reaction forces and lower extremity joint motion during a sauté (dance specific bipedal vertical jump) landing. METHODS: Eighteen …

Portability Vs. Precedent: Imus Vs. 3d Motion Capture For Collecting Kinematic Data In Dancers, Ricardo Tolentino, Gwendolyn R. Retzinger, Stephana Powell, Luis F. Gonzalez, Danielle N. Jarvis

International Journal of Exercise Science: Conference Proceedings

The emergence of portable kinematic data collection systems (Inertial Measurement Units - IMUs) have become a potential alternative to 3D video motion capture systems for real-world application. However, there remains little research on the application of IMU technology for the evaluation of dancers’ biomechanical movement. PURPOSE: To assess the validity of the Noraxon IMU system compared with the Cortex 3D video motion capture system for kinematic data collection during a sauté. METHODS: 10 healthy, advanced female dancers were equipped with both a Noraxon IMU (200Hz) system and reflective markers used with a 12-camera Motion Analysis system (Cortex, 250 …

Effect Of Lead Leg And Fatigue On Ground Reaction Forces In Front Lunges, Jasmyne Holliday, Michele Leblanc

International Journal of Exercise Science: Conference Proceedings

Front lunges are a beneficial exercise that are frequently used for rehabilitation and strength training. In the studies previously conducted, only vertical ground reaction force (GRF) data for the preferred lead leg was analyzed and only male subjects were included (Gao et al., 2022, Park et al., 2021). PURPOSE: The aim of this study was to determine the effect of lead leg and fatigue on lead leg anterior/posterior (Fy) and vertical (Fz) GRFs during the eccentric and concentric phases of the front lunge. METHODS: Ten recreationally active women were recruited and performed front lunges with an assigned step …

Cycling Versus Treadmill Potentiation Effects Following High-Intensity Interval Training, Mark Martinez, Juliet Moore, Kathryn Havens, George Salem

International Journal of Exercise Science: Conference Proceedings

High-intensity interval training (HIIT) has emerged as a popular form of exercise, with intermittent bouts of higher and lower intensity cycles. Not well understood to date is the influence of HIIT exercise modality (e.g., cycling vs treadmill running) on measures of jump performance. A generally accepted metric for assessing performance and overall athleticism involves performing a countermovement jump (CMJ). Furthermore, heavy exercise has been shown to improve muscle performance using post-activation potentiation. Purpose: This study compared the effects of HIIT bouts of cycling vs treadmill running on CMJ concentric impulse, peak takeoff force, and jump height. Methods: Eleven young, …

The Effects Of Heavy Backpack Carriage On Hand Strength, Malea N. Lopez, Jennifer L. Hein, Katherine Saul, Deanna J. Schmidt

International Journal of Exercise Science: Conference Proceedings

Force production in upper limb muscles could be affected following exercise that involves carrying a heavy backpack load. In lower limb muscles, previous study has demonstrated that there is muscle force depression after several different regimens of metabolically and mechanically demanding exercise. PURPOSE: The aim of this study is to examine pinch strength after exercising while carrying a heavy backpack with straps that compress the nerves and blood vessels of the upper limb. We hypothesized that backpack load carriage at 15% body weight and 30% body weight will lead to changes in upper limb lateral pinch strength as compared …

Biomechanical Analysis Of Change Of Direction Movements In Women's Collegiate Soccer Players, Malia Yim, Allie Lam, Travis Peterson

International Journal of Exercise Science: Conference Proceedings

Change of Direction (COD) tasks are common in a variety of high performance sports. PURPOSE: This study aims to determine technique and kinetic differences between unexpected defensive COD tasks in women’s collegiate soccer players. METHODS: Eleven collegiate soccer players participated voluntarily in accordance with the local IRB, performing six 180°R and L , 135° L, and 225°R tasks, approaching from 5m and exiting 3m. Force (Kistler, 1200Hz) and timing information (Brower) data was collected. Repeated Measures ANOVA determined differences across the group between movement directions. RESULTS: Four categories of techniques emerged: natural step, shuffle, hop, and stomp. 135L COD tasks …