Medical Education Commons^™

Action Observation: Olympic Clean & Jerk Skill Acquisition Of Novice Individuals In Virtual Reality, Belle P. Ponce De Leon, Makena Savola, Wendy T. Pham, Rex Ruswick, Rudy Lua, Joshua Vicente

International Journal of Exercise Science: Conference Proceedings

Action observation (AO) involves acquiring skills through watching an expert model demonstrating said skill. Recent developments in virtual reality (VR) technology now allows for a 3D AO viewing perspective. In theory, this allows a learner to view and practice a skill without the requirement of a live demonstrator. While a 360-degree view is not possible through a 2D AO format, it is unknown if it serves as an added benefit or hinderance. PURPOSE: This study explored the viability of using VR for enhancing AO in novice individuals by performing an Olympic weightlifting exercise compared to those engaging in AO …

An Analysis Of Horizontal Forces Between Sports, Riley Neuenburg, Brock Crews, Jared W. Coburn, Kevin Choe

International Journal of Exercise Science: Conference Proceedings

Different sports have various demands that athletes must meet to perform at the requisite level. For example, hockey athletes produce primarily horizontal forces due to skating. However, in basketball, there are a combination of horizontal forces from running and vertical forces from frequent jumping. Therefore, utilizing forces exclusively in one direction as a metric to compare athletes of different sports could provide a limited analysis. PURPOSE: The purpose of this investigation was to compare the relationship between horizontal and vertical forces between athletes who participate in the 4 major sports in the US by using a ratio of horizontal …

Lower Extremity Loading And Subsequent Muscle Soreness Following High-Intensity Interval Training Protocols: A Pilot Study, Jared Moore, Noah Ogata, George Salem

International Journal of Exercise Science: Conference Proceedings

High-intensity interval training (HIIT) is a popular form of exercise that is being performed by the general population as well as athletes. There is little work into how the lower extremity loading within HIIT protocols differs among various exercise modalities and the effects these differences may have on resulting muscle soreness. PURPOSE: The purpose of this pilot study was to characterize lower extremity vertical reaction forces (vRF) during treadmill running and cycling HIIT protocols in young, healthy adults and to explore the relations of the vRF with delayed onset muscle soreness (DOMS). METHODS: Participants completed a heart rate …

Mechanical Differences Between Sexes During A Jump Landing, Miranda Moeslein, Lexy Clark, Jared W. Coburn, Kevin Choe

International Journal of Exercise Science: Conference Proceedings

Jump landings are a frequent occurrence in both male and female sports. However, aberrant landing mechanics, such as landing with smaller knee flexion angles (KFA), can increase the likelihood of knee joint injury. Previous research suggests males and females demonstrate different landing mechanics, which could explain the higher incidence of knee injuries in females, such as anterior cruciate ligament (ACL) injury. PURPOSE: The purpose of this study was to compare lower extremity landing biomechanics associated with ACL injury between males and females. We hypothesized that females would land with smaller KFA and greater knee abduction angles (KAA) compared to males. …

Are There Balance Differences Between Aquatic And Land Athletes?, Bethany Metcalfe, Taylor Garcia, Travis Peterson

International Journal of Exercise Science: Conference Proceedings

Proficiency in static and dynamic balance tests is an indicator of both athletic proficiency as well as an indicator of movement deficiencies. Those movement deficiencies could be due to a neurological issue related to mild traumatic brain injury (i.e. concussion). Previous studies have studied single leg static balance using the BESS (Balance error scoring system) which is also used by the NCAA to pre-test for concussions (Riemann, 2012). Aquatic athletes could be at a predisposed disadvantage in NCAA concussion testing because there is a possibility of having differences in balance ability (as compared to land athletes) that may be mistaken …

Individuals Following Anterior Cruciate Ligament Reconstruction Respond Differently To Limb Loading Instruction: A Clustering Analysis, Willa Ma, Susan Sigward

International Journal of Exercise Science: Conference Proceedings

Individuals following anterior cruciate ligament reconstruction (ACLr) demonstrate altered loading strategies such as shifting mechanical demand away from the surgical knee. Previous work found that individuals can restore limb loading symmetry with instruction to equalize weight distribution between limbs during a squat task. However, when looking at individual responses to these instructions, it appear that not all individual responded similarly. PURPOSE: To use k-means clustering to describe the variation in response to instruction to equalize weight between limbs in individuals 3-4 months post-ACLr. METHODS: We performed a secondary analysis of a dataset including two groups: individuals 110.4 days …

Altered Cortical Activation Patterns In The Motor Cortex Post Acl Reconstruction Compared To Healthy Control, Ryan Kim, Lana Kayali, Abi Rae Stine, Yong Woo An Facsm

International Journal of Exercise Science: Conference Proceedings

Following anterior cruciate ligament reconstruction (ACLR), patients often experience persistent knee dysfunction, such as knee strength deficit, possibly correlated with altered cortical activation in the brain. However, it remains unclear if ACLR patients exhibit different cortical activation patterns in the primary motor cortex (M1) during strength tasks, when compared to healthy control. PURPOSE: To examine electrocortical activation patterns in the M1 during submaximal isometric contraction of the quadriceps between an ACLR patient and a healthy control. METHODS: Both ACLR (female, 21yrs,180.34cm, 77.11kg) and control (female, 39yrs, 160.02cm, 61.23kg) performed isometric extension of the reconstructed or matched knees at …

Impact Of Latin Ballroom Dancing On Gait Biomechanics, Grace Hanks, Tyler Standifird

International Journal of Exercise Science: Conference Proceedings

Purpose: Past research has focused on biomechanical changes, kinematic differences, and injury rates among dancers compared to healthy non-dancers. This research has shown that there are differences biomechanically between dancers and healthy non-dancers which indicates that various forms of dance training has both potential short- and long-term effects on an individual (Yihong et al, 2018, Prochazkova et al, 2014, Tepla et al, 2014, Turner et al 2018). The purpose of this study is to analyze the effect of Latin ballroom dance training on gait. Methods: 24 participants, (12 Latin dancers, 12 recreationally active non-dancers; 12 males,12 females) between the …

The Relationship Between Concussion History And Sex On Lower Extremity Biomechanics During A Cutting Task, Warren O. Forbes, Jason M. Avedesian, Janet S. Dufek

International Journal of Exercise Science: Conference Proceedings

Athletes with a history of sports related concussion (SRC) have been shown to exhibit lower extremity (LE) mechanics during high impact landing tasks that are conducive to increased injury risk. The underlying cause, and extent of this phenomena is currently unknown. PURPOSE: The purpose of this study was to analyze the relationship between SRC history and sex on LE biomechanics during a land-and-cut task. METHODS: College athletes with a history of SRC and a control group of healthy athletes matched by sport, position, sex, and age were recruited for this study. Both groups were comprised of 9 males …

The Effects Of A Heel Lift On Squat Biomechanics, Lexy Clark, Miranda Moeslein, Donovyn Murray, Jared W. Coburn, Kevin Choe

International Journal of Exercise Science: Conference Proceedings

The barbell squat is an effective exercise for improving lower extremity function. During the descent of a squat, the hip and knee joints flex while the ankle joint dorsiflexes. The hip and knee joints then extend and the ankle joint plantarflexes when standing up. During the squat, some athletes use shoes with an elevated heel or other means of heel elevation to achieve lower squat depth. Research has suggested that use of heel elevation may improve range of motion (ROM) of the lower extremity joints and improve stability of the movement during deep squats, especially with an external load. PURPOSE …

Unilateral Load Carriage In Golf Increases Frontal Plane Moment Demand At The Knee, Guanrong Cai, Jordan Cannon, Yunsheng Zou, George Salem

International Journal of Exercise Science: Conference Proceedings

Golf equipment transportation (GET) is a regular task in the sport of golf, a popular activity with more than 66 million participants globally. Unilateral GET is commonly practiced by junior and collegiate golfers, and professional caddies, who incur large walking distances daily, especially during competition. Therefore, the influence of GET on knee mechanics during gait has important implications for performance and injury risks. Furthermore, frontal-plane lower extremity (LE) demands including knee abductor moment during activities may alter knee mechanics and contribute to pain and progression of osteoarthritis (OA). Purpose: To compare the frontal-plane knee moments of two different GET methods …

The Two-Dimensional Relationship Between Ground Reaction Force Vector And Knee Axis Of Rotation Reflect Knee Loading Deficits During Squatting Post-Aclr, Jiaqi Wang, Susan Sigward

International Journal of Exercise Science: Conference Proceedings

PURPOSE

Individuals post-anterior cruciate ligament reconstruction (ACLr) perform reduced knee extensor moments (KEM) during squats by shifting weight to the non-surgical (NSx) limb ¹ or by shifting demands from the knee to hip ^1,2. These compensations occur without observable differences in joint angles by small adjustments in the center of pressure (COP). This makes them difficult to detect and may contribute to their persistence. Differences between limbs in COP position suggest that individuals adjust the relationship of the ground reaction force vector (GRFv) relative to the joint center to redistribute the loading demands in the surgical limb ³. …

The Impact Of Squat Velocity On Force, Power, And Muscle Activity, Kyle D. Puccini, James Baldonado, Bonnie Yee, Christie R. O'Hara

International Journal of Exercise Science: Conference Proceedings

The squat is a thoroughly examined movement pattern and commonly used in sport performance training protocols, rehabilitation programs, and recreational exercise. Previous research measuring absolute strength has shown hamstring muscle activity in a six-repetition max barbell back squats. PURPOSE: The purpose of this study is to examine the effects of varying squat velocities (25, 50, 75 deg/s) on force, power, and the activation of the quadricep and hamstring muscles. Using a single-blind randomized research design, we hypothesized that hamstring muscle activity will increase at faster squat velocities. Our secondary hypothesis is that peak power will occur at 50 deg/s and …

Laboratory Measurements Of Division 1 College Baseball Players To Predict Field Base Performance, Sebastian Ortiz, Lyric Richardson, Emma Bozarth, Amy Riera, Kase Pennartz, Micheal Luera

International Journal of Exercise Science: Conference Proceedings

Cross-sectional area (CSA) of skeletal muscle has been commonly used as a predictor of force production. Peak force (PF) production during maximal contractions of the lower body can be a primary indicator of an athlete’s potential to perform on the field. PURPOSE: The purpose of this study was to use CSA for the VL and RF and PF to predict 60-yard dash times. METHODS: Fifteen male athletes (20.64 yrs. ±1.54, 182.89 cm. ±5.74, 196.58 kg ±21.2.) participated in this investigation. Sixty-yard dash times were recorded from each athlete prior to laboratory testing. Skeletal muscle CSA were taken from the VL …

Monitoring Firing Behaviors Of Motor Unit Action Potentials During Low-Intensity Fatiguing Contractions, Dakota Harris, Lyric Richardson, Amy Riera, Emma Bozarth, Micheal Luera

International Journal of Exercise Science: Conference Proceedings

Motor Units (MU) are systematically activated from increasing size in accordance to the size principle. As muscle fatigue sets in, MU firing rate increases in response to sustaining whole-body force production during a low-loaded sustained contraction with respect to MU size and MU interspike intervals (ISI). PURPOSE: The purpose of this study is to compare the motor unit firing behaviors during low-force isometric fatiguing contractions. Methods: Following 3 MVCs, eight lower-body resistance trained males (23.38 ± 2.88 yrs.; 178.38 ± 7.85 cm; 86.10 ± 11.88 kg) performed 60 second submaximal (30% MVC) isometric ramp contraction of the knee extension …

Lower Extremity Muscle Activity When Walking On A Non-Motorized Treadmill, Carl P. Shaulis, Sam I. Anderson, Riley A. Barlage, Scott P. Mclean

International Journal of Exercise Science: Conference Proceedings

Effective interventions for increasing walking speed are important for improving health and quality of life in aging populations. Non-motorized treadmills (NMT) may enhance the ability to develop or improve motor control in gait by requiring the participant to produce and maintain speed as compared to use of a motorized treadmill (MT) which requires one to simply match speed. PURPOSE: The purpose of this project was to compare muscle activation patterns of lower extremity muscles between MT, NMT and overground (OG) walking. METHODS: Twenty healthy adults (24.4±7.2 yrs, 1.75±0.09 m, 75.4±13.1 kg) completed one trial of walking at each …

Cortical Activity Measured With Low-Intensity Fatiguing Contractions Of The Quadriceps Muscle Group, Emma D. Bozarth, Lyric D. Richardson, Amy E. Riera, Micheal J. Luera, Amber H. Bozer

International Journal of Exercise Science: Conference Proceedings

Modulation of force production required during exercise is regulated from various mechanisms in the central and peripheral nervous system. Fatigue is influenced by various mechanics that may hinder the ability to continuously sustain force production. The neural activation patterns of these systems can be recorded as electrical impulses using several non-invasive techniques. The ability to examine these during fatiguing exercise has provided further insight into activation patterns in the central nervous system (i.e., motor and pre-motor cortex) during sustained muscle contractions. Electroencephalography (EEG) has been recently utilized to examine changes associated with central fatigue, but limited advancements in technology for …

Effects Of Low-Intensity Fatigue On Motor Unit Firing Properties During Maximal Voluntary Isometric Contractions, Lyric Richardson, Amy Riera, Emma Bozarth, Micheal Luera

International Journal of Exercise Science: Conference Proceedings

Rehabilitation from injuries impairing the neuromuscular system is often difficult to quantify due to task specificity of the affected or immobilized limb or limbs. Often, exercise regimens with clinical practitioners are designed to progress motor performance to a capacity that reflects muscle force production to pre-injury capacity. Modulation of force production from these tasks are regulated from various mechanism in the central and peripheral nervous system. The neural activation of these systems can be recorded as electrical impulses using several non-invasive techniques. Recently, the ability to examine these during fatiguing exercise has provided further insight into activation patterns and firing …

Lifting In An Alternate Reality: The Application Of Action Observation Within Virtual Reality And Weightlifting., Michael Weise, Nikko Cando, Alex Krause, Kim Hernandez, Rabbani Nzeza, Allyssa Alcasabas, Jake Hinkel-Lipsker

International Journal of Exercise Science: Conference Proceedings

Action observation (AO), where a learner watches a model perform a skill, has long been shown to facilitate motor learning of a variety of skills. There is great interest in learning ways to optimize the AO experience in order to maximize motor learning. In recent years, virtual reality (VR) technology has advanced considerably, where high-fidelity environments can facilitate a fully immersive experience. As such, the three-dimensional (3D) VR experience could allow for improved learning through AO over more traditional forms (e.g., watching a computer screen). PURPOSE: The purpose of this study is to determine how well people learn a …

Obstacle Negotiation Gaze Strategies Of The Physically Fatigued, Belle P. Ponce De Leon, Makena Savola, Sedona Boren, Andrew Fishman, Sarika Varma, Jacob W. Hinkel-Lipsker

International Journal of Exercise Science: Conference Proceedings

INTRODUCTION: Proper obstacle negotiation while in a fatigued state is a safety concern for first responders, firefighters and other primary relief personnel in their high-risk line of work. During locomotion the central gaze is focused beyond the obstacle to plan future steps while the peripheral vision spatially tracks the obstacle. Previous work indicates that following intense exercise people experience a narrowed peripheral visual field, making them more reliant on central gaze. Thus, it is possible that when physically-fatigued people become more reliant on central gaze to perceive obstacles, leaving them unable to plan future steps as effectively.

PURPOSE: This study …

The Impact Of Anterior Cruciate Ligament Injury Risk On Baseline Balance Assessment For Concussion In Collegiate Athletes, Ryan N. Moran, Nicholas G. Murray

International Journal of Exercise Science: Conference Proceedings

PURPOSE: Recent literature has linked concussion and neuromuscular deficits in the lower extremity after injury. Neuromuscular control is frequently assessed using balance measures for concussion, but also dynamically to identify anterior cruciate ligament injury (ACL) risk via jump-landing movement screening. The purpose of this study was to examine the impact of ACL injury risk on baseline balance assessment for concussion. METHODS: Thirty-nine healthy, collegiate female soccer (n=22) and volleyball (n=17) athletes completed the modified-Clinical Test of Sensory Interaction of Balance (m-CTSIB) and the Landing Error Scoring System (LESS) test as part of routine concussion baseline testing and injury …

Effects Of Short Foot Exercise On Ankle Eversion Velocity, Daniel Metri, Jacob Mayoral, Connor Owen, Andy Arant, Dane Johnson, Robert Dudley, Andrea Du Bois

International Journal of Exercise Science: Conference Proceedings

The biomechanical position of the foot while landing plays a major role in performance and injury. A common issue of landing is excessive foot pronation and subsequently ankle eversion. This biomechanical position can result in knee abduction, increasing the chance of knee injury. The velocity at which the ankle everts may also be a component of injury as long distance runners that became injured had higher ankle eversion velocity in their landing strides while running. Short foot exercise (SFE) strengthens the intrinsic muscles of the foot and help stabilize the arch which assists in eccentrically controlling pronation. However, acute effects …

Uphill, Level, And Downhill Running In A New Style Of Road-Racing Shoe, Hunter Mcwilliams, Iain Hunter, Jared Ward, Cal Bradshaw, Tyler Standifird

International Journal of Exercise Science: Conference Proceedings

Recent changes in road-racing shoe construction has prompted research comparing the metabolic benefit of new shoe constructions compared to older styles. Kinematic and kinetic changes with uphill and downhill running may affect the magnitude of benefit for this new style of racing shoe. PURPOSE: Due to the changes associated with downhill running, we hypothesize that new performance racing shoes will have a greater metabolic benefit when running downhill, than with level or uphill running. METHODS: Eighteen subjects (10 men and 8 women) ran on two separate days with shoe order reversed. They wore either the Saucony Type A …

The Effect Of The Short Foot Exercise On The Knee During Landing, Jacob G. Mayoral, Connor Owen, Daniel Metri, Andy Arant, Dane Johnson, Robert Dudley, Andrea Du Bois

International Journal of Exercise Science: Conference Proceedings

Intrinsic foot muscles play an important role in the stabilization of the foot and assist with pronation of the foot. Excessive eversion, a component of pronation, may carry up the kinetic chain to impact the knee’s frontal plane position, increasing the chance of a knee injury. Runners who go on to sustain injuries have a greater peak knee abduction moment during running than those without injury. Regular short foot exercise (SFE) strengthens the intrinsic foot muscles, which over time could help improve foot posture and mechanics up the kinetic chain. It is unclear if a single bout of SFE can …

Short-Term Effects Of Exercise On Grip And Pinch Strength, Kristen Lantis, Deanna J. Schmidt

International Journal of Exercise Science: Conference Proceedings

PURPOSE: Occupations such as first responders and military may require use of hand and finger muscles after exercise, therefore changes in grip strength (GS) and pinch strength (PS) could affect task performance. While previous studies have shown decreases in GS with load carriage, others have shown increases in GS with other forms of exercise. The purpose of this study is to examine the short-term changes in GS and PS with exercise and load carriage. METHODS: Seven participants to date (5 male, 2 female; mean ± SD of 25.1 ± 4.5 yrs, 176.9 ± 11.9 cm height; 80.6 ± …

Angular Impulse Of The Whole Body During American Football Long Snapping, Janelle J. Kim, Travis J. Peterson

International Journal of Exercise Science: Conference Proceedings

Long snapping is found in American football, and the goal is to have the ball reach the punter as quickly and accurately as possible so they can kick the ball downfield with minimal interference from the opposing team. Little research has been performed on the whole body kinetics of long snapping. PURPOSE: To describe the differences in angular impulse between high school and college athletes during the act of long snapping. METHODS: This study compared high school long snappers (n=5) and college long snappers (n=5). Whole group average age (18.9 ± 1.3 years), years of long snapping experience …

A Case Study Comparison Of Lower Extremity Kinematics In Medial Tibial Stress Syndrome, Amanda Hernandez, Patricia Vanoosbree, Kristyne Wiegand

International Journal of Exercise Science: Conference Proceedings

Medial tibial stress syndrome (MTSS) affects up to 35% of runners. Chronic MTSS can negatively affect performance or lead to a cessation of activity. Though biomechanical variables such as hip internal rotation, tibial abduction, and rearfoot eversion are considered potential risk factors for MTSS, the research is equivocal. PURPOSE: Therefore, the purpose of this case analysis is to compare lower extremity kinematics of a D3 middle-distance runner with chronic MTSS vs. a matched uninjured runner. METHODS: This case study consists of two female middle-distance runners. Participant one (19 y.o., 1.73 m, 70.3 kg) experienced intermittent MTSS for 4 years. …

Quality Of Knee Strengthening Exercises Performed At Home Deteriorates After One Week, Hayden E. Dennis, Hyunwook Lee, Ulrike Mitchell, M. K. Seeley

International Journal of Exercise Science: Conference Proceedings

Current clinical practice guidelines for physical therapy (PT) post-total knee arthroplasty (TKA) recommend supervised postoperative PT; this recommendation is based on research demonstrating that more direct supervision from a physical therapist yields improved mobility, balance, and overall quality-of-life, relative to less supervision. Supervised post-operative PT is not always feasible due to non-availability of a licensed physical therapist, lack of health insurance, and/or other factors. Consequently, patients often perform post-TKA PT exercises without supervision. PURPOSE: To compare the quality (determined via the ability to replicate lower extremity kinematics recommended by a physical therapist) of post-TKA PT exercises in healthy older …

Electromyographic Analysis Of The Vastus Lateralis And Vastus Medialis Muscles Among Different Crank Lengths In Cycling, Jackson C. Crovella, Karoline M. Wucherer, Joy He, Christiane R. O'Hara

International Journal of Exercise Science: Conference Proceedings

Crank length (CL) on a bicycle may influence the total activation and period of activation of the leg muscles. Differences in total muscular activation suggest that CL may alter muscular fatigue. Differences in muscular onset and offset suggest that CL may shift muscle activation periods across a 360 degree crank cycle. PURPOSE: To examine the effects of four different CL (155, 165, 175, and 185 mm) on muscular activation of vastus lateralis (VL) and vastus medialis (VM). METHODS: Nine non-cyclists (6M, 3F, aged 18-55) participated in a single blind randomized cross-over experiment with four CL. Delsys EMG sensors …

Effects Of An Achilles Speedbridge On Ankle Joint Motion: A Case Study, Alfredo Cervantes, Kevin Valenzuela, Justin Demoss, Anaya Blade, Hunter J. Bennett

International Journal of Exercise Science: Conference Proceedings

Over 80% of Achilles injuries are related to individuals who participate in sports or recreational activities that involve either jumping or running. Current research does not provide insight into the longitudinal recovery effects following an Achilles repair surgery. PURPOSE: To evaluate the longitudinal effects of lower extremity kinematics following an Achilles Speedbridge surgery. METHODS: A 35-year-old male (1.85m, 86.4kg) presented right Achilles insertional tendinitis and a large retrocalcaneal bone spur which had fractured and was partially embedded in the Achilles tendon. One week prior to operation the subject completed over ground walking trials at 1.0 m/s velocity. Following …