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Randomized Controlled Trial Of The Behavioral Intervention For Increasing Physical Activity In Multiple Sclerosis Project: Secondary, Patient-Reported Outcomes, Robert W. Motl, Brian M. Sandroff, Lara A. Pilutti, Gary R. Cutter, Roberto Aldunate, Ariel Kidwell, Rachel E. Bollaert Feb 2023

Randomized Controlled Trial Of The Behavioral Intervention For Increasing Physical Activity In Multiple Sclerosis Project: Secondary, Patient-Reported Outcomes, Robert W. Motl, Brian M. Sandroff, Lara A. Pilutti, Gary R. Cutter, Roberto Aldunate, Ariel Kidwell, Rachel E. Bollaert

Exercise Science Faculty Research and Publications

Background

We undertook a randomized controlled trial (RCT) that investigated the effectiveness of a theory-based, Internet-delivered, behavioral intervention focusing on physical activity promotion for immediate and sustained improvements in secondary, patient-reported outcomes (PROs) of function, symptoms, and quality of life (QOL) in multiple sclerosis (MS).

Method

Persons with MS (N = 318) were recruited from throughout the United States and randomized into behavioral intervention (n = 159) or attention/social contact control (n = 159) conditions. The conditions were administered over a 6-month period by persons who were uninvolved in screening, recruitment, random assignment, and outcome assessment. There …


Depression, Anxiety, And Physical Activity In Older Adults With Multiple Sclerosis, Rachel E. Bollaert, C. Danielle Jones, Petra Silic, Robert W. Motl Feb 2023

Depression, Anxiety, And Physical Activity In Older Adults With Multiple Sclerosis, Rachel E. Bollaert, C. Danielle Jones, Petra Silic, Robert W. Motl

Exercise Science Faculty Research and Publications

This study examined levels of depression and anxiety symptoms (Hospital Anxiety and Depression Scale scores), and self-reported (Godin Leisure-Time Exercise Questionnaire), and accelerometer-measured physical activity in older adults with multiple sclerosis (n = 40) compared with age- and sex-matched healthy controls (n = 40). We observed differences in depression, anxiety, and physical activity between groups and further observed that minutes/day of moderate to vigorous physical activity partially accounted for group differences in depression scores. We provide preliminary support for research examining approaches for increasing moderate to vigorous physical activity and possibly reducing depression symptoms in older adults with …


Who Was Wearing A Mask In 2021? Update On Gender-, Age-, And Location-Related Differences During The Covid-19 Pandemic, Michael H. Haischer, Rachel Beilfuss, Meggie Rose Hart, Lauren Opielinski, Emma Schmit, David Wrucke, Helena Zhao, Toni D. Uhrich, Sandra K. Hunter Jan 2023

Who Was Wearing A Mask In 2021? Update On Gender-, Age-, And Location-Related Differences During The Covid-19 Pandemic, Michael H. Haischer, Rachel Beilfuss, Meggie Rose Hart, Lauren Opielinski, Emma Schmit, David Wrucke, Helena Zhao, Toni D. Uhrich, Sandra K. Hunter

Exercise Science Faculty Research and Publications

Previous observational work from 2020 demonstrated gender-, age-, and location-related differences in mask-wearing behavior, despite the efficacy and public health messaging that emphasized face coverings in combatting the spread of COVID-19. In 2021, COVID-19 vaccinations and a corresponding change in public health policy became new considerations in deciding personal protective behaviors. To provide an update on mask wearers and resistors approximately one year after our initial study, we observed shoppers (n = 6,118) entering retail stores using the same experimental methodology. Approximately 26% of individuals wore a mask. Mask wearing has decreased across demographic groups compared to 2020. Aligning …


Moderate-To-Vigorous Physical Activity Is Related With Retinal Neuronal And Axonal Integrity In Persons With Multiple Sclerosis, Jeongwoon Kim, Rachel E. Bollaert, Jonathan Cerna, Brynn C. Adamson, Connor M. Robbs, Naiman A. Khan, Robert W. Motl Dec 2022

Moderate-To-Vigorous Physical Activity Is Related With Retinal Neuronal And Axonal Integrity In Persons With Multiple Sclerosis, Jeongwoon Kim, Rachel E. Bollaert, Jonathan Cerna, Brynn C. Adamson, Connor M. Robbs, Naiman A. Khan, Robert W. Motl

Exercise Science Faculty Research and Publications

Background

Moderate-to-vigorous physical activity (MVPA) may confer benefits for axonal and/or neuronal integrity in adults with multiple sclerosis (MS).

Purpose

Examine the association between device-measured MVPA with optical coherence tomography (OCT) metrics of retinal nerve fiber layer (RNFL) thickness and total macular volume (TMV) in persons with and without MS.

Methods

Adults with MS (N = 41), along with sex-matched healthy control (HC) participants (N = 79), underwent measurements of retinal morphology via OCT and wore an accelerometer for a period of 7 days as a measure of MVPA.

Results

Persons with MS had significantly lower MVPA, RNFL thickness, and …


Muscle-Specific Contributions To Lower Extremity Net Joint Moments While Squatting With Different External Loads, Kristof Kipp, Hoon Kim, William I. Wolf Feb 2022

Muscle-Specific Contributions To Lower Extremity Net Joint Moments While Squatting With Different External Loads, Kristof Kipp, Hoon Kim, William I. Wolf

Exercise Science Faculty Research and Publications

The purpose of this study was to determine muscle-specific contributions to lower extremity net joint moments (NJMs) during squats with different external loads. Nine healthy subjects performed sets of the back squat exercise with 0, 25, 50, and 75% of body mass as an added external load. Motion capture and force plate data were used to calculate NJMs and to estimate individual muscle forces via static optimization. Individual muscle forces were multiplied by their respective moment arms to calculate the resulting muscle-specific joint moment. Statistical parametric mapping (α = 0.05) was used to determine load-dependent changes in the time series …


Maximal Strength In Relation To Force And Velocity Patterns During Countermovement Jumps, Michael H. Haischer, John Krzyszkowski, Stuart Roche, Kristof Kipp Jan 2022

Maximal Strength In Relation To Force And Velocity Patterns During Countermovement Jumps, Michael H. Haischer, John Krzyszkowski, Stuart Roche, Kristof Kipp

Exercise Science Faculty Research and Publications

Maximal strength is important for the performance of dynamic athletic activities, such as countermovement jumps (CMJ). Although measures of maximal strength appear related to discrete CMJ variables, such as peak ground reaction forces (GRF) and center-of-mass (COM) velocity, knowledge about the association between strength and the time series patterns during CMJ will help characterize changes that can be expected in dynamic movement with changes in maximal strength. Purpose: To investigate the associations between maximal strength and GRF and COM velocity patterns during CMJ. Methods: Nineteen female college lacrosse players performed 3 maximal-effort CMJs and isometric midthigh pull. GRF …


Hip And Knee Joint Angle Patterns And Kicking Velocity In Female And Male Professional Soccer Players: A Principal Component Analysis Of Waveforms Approach, Archit Navandar, Kristof Kipp, Enrique Navarro Jan 2022

Hip And Knee Joint Angle Patterns And Kicking Velocity In Female And Male Professional Soccer Players: A Principal Component Analysis Of Waveforms Approach, Archit Navandar, Kristof Kipp, Enrique Navarro

Exercise Science Faculty Research and Publications

This study used principal component analysis (PCA) of waveforms to extract movement patterns from hip and knee angle time-series data; and determined if the extracted movement patterns were predictors of ball velocity during a soccer kick. Twenty-three female and nineteen male professional soccer players performed maximal effort instep kicks while motion capture and post-impact ball velocities data were recorded. Three-dimensional hip and knee joint angle time-series data were calculated from the beginning of the kicking leg’s backswing phase until the end of the follow-through phase and entered into separate PCAs for females and males. Three principal components (PC) (i.e., movement …


Accuracy Of Body Mass Index In Categorizing Weight Status In Children With Intellectual And Developmental Disabilities, Michele Polfuss, Bethany Forseth, Dale A. Schoeller, Chiang-Ching Huang, Andrea Moosreiner, Paula E. Papanek, Kathleen J. Sawin, Kimberley Zvara, Linda Bandini Dec 2021

Accuracy Of Body Mass Index In Categorizing Weight Status In Children With Intellectual And Developmental Disabilities, Michele Polfuss, Bethany Forseth, Dale A. Schoeller, Chiang-Ching Huang, Andrea Moosreiner, Paula E. Papanek, Kathleen J. Sawin, Kimberley Zvara, Linda Bandini

Exercise Science Faculty Research and Publications

PURPOSE:

To identify the accuracy of Body Mass Index (BMI) to categorize body weight in a sample of children with spina bifida and Down syndrome as compared to typically developing peers.

METHODS:

A secondary analysis of 32 children with spina bifida, Down syndrome or no chronic illness. A calculated BMI was plotted on the Centers for Disease Control and Prevention age- and sex-specific BMI growth charts to determine each child’s weight status. Percentage of body fat, obtained by labeled water, was plotted on two different body fat percentile reference curves, one derived from a whole body measure (DXA) of body …


Influence Of The Bar Position On Joint-Level Biomechanics During Isometric Pulling Exercises, Nayun Ahn, Hoon Kim, John Krzyszkowski, Stuart Roche, Kristof Kipp Jun 2021

Influence Of The Bar Position On Joint-Level Biomechanics During Isometric Pulling Exercises, Nayun Ahn, Hoon Kim, John Krzyszkowski, Stuart Roche, Kristof Kipp

Exercise Science Faculty Research and Publications

The purpose of this study was to investigate the influence of the bar position on ankle, knee, and hip net joint moments (NJMs), relative muscular effort (RME), and vertical ground reaction forces (GRFs) during isometric pulling exercises, such as the isometric midthigh pull. Eight female lacrosse athletes performed maximal effort isometric pulls at 3 different bar positions (low: above patella, mid: midthigh, and high: crease of hip) while motion capture and GRF data were recorded. Net joint moments were calculated with inverse dynamics. Relative muscle effort was defined as the ratio between the inverse dynamics NJMs and the maximum theoretical …


Phase-Iii, Randomized Controlled Trial Of The Behavioral Intervention For Increasing Physical Activity In Multiple Sclerosis: Project Bipams, Robert W. Motl, Brian M. Sandroff, Brooks C. Wingo, Justin Mccroskey, Lara A. Pilutti, Gary R. Cutter, Rachel Bollaert, Edward Mcauley Aug 2018

Phase-Iii, Randomized Controlled Trial Of The Behavioral Intervention For Increasing Physical Activity In Multiple Sclerosis: Project Bipams, Robert W. Motl, Brian M. Sandroff, Brooks C. Wingo, Justin Mccroskey, Lara A. Pilutti, Gary R. Cutter, Rachel Bollaert, Edward Mcauley

Exercise Science Faculty Research and Publications

Background

We propose a phase-III, randomized controlled trial (RCT) that examines the effectiveness of a behavioral intervention based on social cognitive theory (SCT) and delivered through the Internet using e-learning approaches for increasing physical activity and secondary outcomes (e.g., symptoms) in a large sample of people with multiple sclerosis (MS) residing throughout the United States.

Methods/design

The proposed phase-III trial will use a parallel group, RCT design that examines the effect of a 6-month behavioral intervention for increasing physical activity and secondarily improving mobility, cognition, symptoms, and quality of life (QOL) in persons with MS. The primary outcome is accelerometer-measured …


Total Energy Expenditure And Body Composition Of Children With Developmental Disabilities, Michele L. Polfuss, Kathleen J. Sawin, Paula E. Papanek, Linda Bandini, Bethany Forseth, Andrea Moosreiner, Kimberley Zvara, Dale A. Schoeller Jul 2018

Total Energy Expenditure And Body Composition Of Children With Developmental Disabilities, Michele L. Polfuss, Kathleen J. Sawin, Paula E. Papanek, Linda Bandini, Bethany Forseth, Andrea Moosreiner, Kimberley Zvara, Dale A. Schoeller

Exercise Science Faculty Research and Publications

Background

Obesity prevalence is increased in children with developmental disabilities, specifically in children with spina bifida and Down syndrome. Energy expenditure, a critical aspect of weight management, has been extensively studied in the typically developing population, but not adequately studied in children with developmental disabilities.

Objective

Determine energy expenditure, fat-free mass and body fat percentile and the impact of these findings on recommended caloric intake in children with spina bifida and Down syndrome.

Methods/Measures

This pilot study included 36 children, 18 with spina bifida, 9 with Down syndrome and 9 typically developing children. Half of the children with spina bifida …


Sex Differences In Mechanisms Of Recovery After Isometric And Dynamic Fatiguing Tasks, Jonathon Senefeld, Hugo M. Pereira, Nicholas Elliott, Tejin Yoon, Sandra K. Hunter May 2018

Sex Differences In Mechanisms Of Recovery After Isometric And Dynamic Fatiguing Tasks, Jonathon Senefeld, Hugo M. Pereira, Nicholas Elliott, Tejin Yoon, Sandra K. Hunter

Exercise Science Faculty Research and Publications

Purpose The purpose of this study was to determine whether supraspinal mechanisms contribute to the sex difference in fatigability during and recovery from a dynamic and isometric fatiguing task with the knee extensors.

Methods: Transcranial magnetic stimulation and electrical stimulation were used to determine voluntary activation and contractile properties of the knee extensors in 14 men and 17 women (20.8 ± 1.9 yr) after a 1) 60-s sustained, maximal voluntary isometric contraction (MVIC), and 2) dynamic fatiguing task involving 120 maximal voluntary concentric contractions with a 20% MVIC load.

Results: There were no differences between men and women in the …


Sex Differences In Neuromuscular Fatigability Of The Knee Extensors Post-Stroke, Meghan Kirking, Reivian B. Barillas, Philip A. Nelson, Sandra K. Hunter, Allison Hyngstrom Jan 2017

Sex Differences In Neuromuscular Fatigability Of The Knee Extensors Post-Stroke, Meghan Kirking, Reivian B. Barillas, Philip A. Nelson, Sandra K. Hunter, Allison Hyngstrom

Exercise Science Faculty Research and Publications

Background and Purpose: Despite the implications of optimizing strength training post-stroke, little is known about the differences in fatigability between men and women with chronic stroke. The purpose of this study was to determine the sex differences in knee extensor muscle fatigability and potential mechanisms in individuals with stroke. Methods: Eighteen participants (10 men, eight women) with chronic stroke (≥6 months) and 23 (12 men, 11 women) nonstroke controls participated in the study. Participants performed an intermittent isometric contraction task (6 s contraction, 3 s rest) at 30% of maximal voluntary contraction (MVC) torque until failure to maintain the target …


Muscle Function And Fatigability Of Trunk Flexors In Males And Females, Rita Deering, Jonathon Senefeld, Tatyana Pashibin, Donald A. Neumann, Sandra K. Hunter Jan 2017

Muscle Function And Fatigability Of Trunk Flexors In Males And Females, Rita Deering, Jonathon Senefeld, Tatyana Pashibin, Donald A. Neumann, Sandra K. Hunter

Exercise Science Faculty Research and Publications

Background

Optimal function of the abdominal muscles is necessary for several life functions including lifting and carrying tasks. Sex differences in strength and fatigability are established for many limb muscles and back extensor muscles, but it is unknown if sex differences exist for the abdominal muscles despite their functional importance.

Methods

Eighteen females (24.3 ± 4.8 years) and 15 males (24.1 ± 6.6 years) performed (1) isometric trunk flexion maximal voluntary contractions (MVCs) in a range of trunk positions to establish a torque-angle curve and (2) submaximal (50% MVC), intermittent isometric contraction (6 s on, 4 s off) until task …


Wellness And Multiple Sclerosis: The National Ms Society Establishes A Wellness Research Working Group And Research Priorities, Robert W. Motl, Ellen M. Mowry, Dawn M. Ehde, Nicholas G. Larocca, Kathy E. Smith, Kathleen Costello, Lynne Shinto, Alex V. Ng, Amy B. Sullivan, Barbara Geisser, Kevin K. Mccully, Bo Fernhall, Malachy Bishop, Matthew Plow, Patrizia Casaccia, Nancy D. Chiaravalloti Jan 2017

Wellness And Multiple Sclerosis: The National Ms Society Establishes A Wellness Research Working Group And Research Priorities, Robert W. Motl, Ellen M. Mowry, Dawn M. Ehde, Nicholas G. Larocca, Kathy E. Smith, Kathleen Costello, Lynne Shinto, Alex V. Ng, Amy B. Sullivan, Barbara Geisser, Kevin K. Mccully, Bo Fernhall, Malachy Bishop, Matthew Plow, Patrizia Casaccia, Nancy D. Chiaravalloti

Exercise Science Faculty Research and Publications

Background:

People with multiple sclerosis (MS) have identified “wellness” and associated behaviors as a high priority based on “social media listening” undertaken by the National MS Society (i.e. the Society).

Objective:

The Society recently convened a group that consisted of researchers with experience in MS and wellness-related research, Society staff members, and an individual with MS for developing recommendations regarding a wellness research agenda.

Method:

The members of the group engaged in focal reviews and discussions involving the state of science within three approaches for promoting wellness in MS, namely diet, exercise, and emotional wellness.

Results:

That process informed a …


Mechanical Demands Of The Hang Power Clean And Jump Shrug: A Joint-Level Perspective, Kristof Kipp, Philip Malloy, Jordan Smith, Matthew D. Giordanelli, Michael T. Kiely, Christopher Geiser, Timothy J. Suchomel Sep 2016

Mechanical Demands Of The Hang Power Clean And Jump Shrug: A Joint-Level Perspective, Kristof Kipp, Philip Malloy, Jordan Smith, Matthew D. Giordanelli, Michael T. Kiely, Christopher Geiser, Timothy J. Suchomel

Exercise Science Faculty Research and Publications

The purpose of this study was to investigate the joint- and load-dependent changes in the mechanical demands of the lower extremity joints during the hang power clean (HPC) and the jump shrug (JS). Fifteen male lacrosse players were recruited from an NCAA DI team, and completed three sets of the HPC and JS at 30%, 50%, and 70% of their HPC 1-Repetition Maximum (1-RM HPC) in a counterbalanced and randomized order. Motion analysis and force plate technology were used to calculate the positive work, propulsive phase duration, and peak concentric power at the hip, knee, and ankle joints. Separate three-way …


Muscle-Specific Effective Mechanical Advantage And Joint Impulse In Weightlifting, Kristof Kipp, Chad Harris Sep 2016

Muscle-Specific Effective Mechanical Advantage And Joint Impulse In Weightlifting, Kristof Kipp, Chad Harris

Exercise Science Faculty Research and Publications

Lifting greater loads during weightlifting exercises may theoretically be achieved through increasing the magnitudes of net joint impulses or manipulating the joints’ effective mechanical advantage (EMA). The purpose of this study was to investigate muscle-specific EMA and joint impulse as well as impulse-momentum characteristics of the lifter-barbell system across a range of external loads during the execution of the clean. Collegiate-level weightlifters performed submaximal cleans at 65, 75, and 85% of their 1-repetition maximum (1-RM) while data from a motion analysis system and a force plate were used to calculate lifter-barbell system impulse and velocity, as well as net extensor …


Hip External Rotator Strength Is Associated With Better Dynamic Control Of The Lower Extremity During Landing Tasks, Philip Malloy, Alexander Morgan, Carolyn M. Meinerz, Christopher Geiser, Kristof Kipp Jan 2016

Hip External Rotator Strength Is Associated With Better Dynamic Control Of The Lower Extremity During Landing Tasks, Philip Malloy, Alexander Morgan, Carolyn M. Meinerz, Christopher Geiser, Kristof Kipp

Exercise Science Faculty Research and Publications

Hip external rotator strength is associated with better dynamic control of the lower extremity during landing tasks. J Strength Cond Res 30(1): 282–291, 2016—The purpose of this study was to determine the association between hip strength and lower extremity kinematics and kinetics during unanticipated single-leg landing and cutting tasks in collegiate female soccer players. Twenty-three National Collegiate Athletic Association division I female soccer players were recruited for strength testing and biomechanical analysis. Maximal isometric hip abduction and external rotation strength were measured using a hand-held dynamometer and expressed as muscle torque (force × femoral length) and normalized to body weight. …


Body Composition Measurement In Children With Cerebral Palsy, Spina Bifida And Spinal Cord Injury: A Systematic Review Of The Literature, Michele L. Polfuss, Paula E. Papanek, Fallon Meyer-Wentland, Andrea Moosreiner, Lenore R. Wilkas, Kathleen J. Sawin Jan 2016

Body Composition Measurement In Children With Cerebral Palsy, Spina Bifida And Spinal Cord Injury: A Systematic Review Of The Literature, Michele L. Polfuss, Paula E. Papanek, Fallon Meyer-Wentland, Andrea Moosreiner, Lenore R. Wilkas, Kathleen J. Sawin

Exercise Science Faculty Research and Publications

Pediatric obesity is a major health concern that has an increased prevalence in children with special needs. In order to categorize a child’s weight, an assessment of body composition is needed. Obtaining an accurate body composition measurement in children with special needs has many challenges associated with it. This perplexing scenario limits the provider’s ability to screen, prevent and treat an abnormal weight status in this vulnerable population. This systematic review summarizes common methods of body composition measurements, their strengths and limitations and reviews the literature when measurements were used in children with cerebral palsy, spina bifida and spinal cord …


Impaired Hyperemic Response To Exercise Post Stroke, Matthew J. Durand, Spencer A. Murphy, Kathleen K. Schaefer, Sandra K. Hunter, Brian D. Schmit, David D. Gutterman, Allison Hyngstrom Dec 2015

Impaired Hyperemic Response To Exercise Post Stroke, Matthew J. Durand, Spencer A. Murphy, Kathleen K. Schaefer, Sandra K. Hunter, Brian D. Schmit, David D. Gutterman, Allison Hyngstrom

Exercise Science Faculty Research and Publications

Individuals with chronic stroke have reduced perfusion of the paretic lower limb at rest; however, the hyperemic response to graded muscle contractions in this patient population has not been examined. This study quantified blood flow to the paretic and non-paretic lower limbs of subjects with chronic stroke after submaximal contractions of the knee extensor muscles and correlated those measures with limb function and activity. Ten subjects with chronic stroke and ten controls had blood flow through the superficial femoral artery quantified with ultrasonography before and immediately after 10 second contractions of the knee extensor muscles at 20, 40, 60, and …


Stroke-Related Effects On Maximal Dynamic Hip Flexor Fatigability And Functional Implications, Henry Kuhnen, Megan M. Rybar, Tanya Onushko, Ryan E. Doyel, Sandra K. Hunter, Brian D. Schmit, Allison Hyngstrom Mar 2015

Stroke-Related Effects On Maximal Dynamic Hip Flexor Fatigability And Functional Implications, Henry Kuhnen, Megan M. Rybar, Tanya Onushko, Ryan E. Doyel, Sandra K. Hunter, Brian D. Schmit, Allison Hyngstrom

Exercise Science Faculty Research and Publications

Introduction: Stroke-related changes in maximal dynamic hip flexor muscle fatigability may be more relevant functionally than isometric hip flexor fatigability. Methods: Ten chronic stroke survivors performed 5 sets of 30 hip flexion maximal dynamic voluntary contractions (MDVC). A maximal isometric voluntary contraction (MIVC) was performed before and after completion of the dynamic contractions. Both the paretic and nonparetic legs were tested. Results: Reduction in hip flexion MDVC torque in the paretic leg (44.7%) was larger than the nonparetic leg (31.7%). The paretic leg had a larger reduction in rectus femoris EMG (28.9%) between the first and last …


The Stroke-Related Effects Of Hip Flexion Fatigue On Over Ground Walking, Megan M. Rybar, Eric R. Walker, Henry Kuhnen, Daniel R. Ouellette, Reivian Berrios, Sandra K. Hunter, Allison Hyngstrom Apr 2014

The Stroke-Related Effects Of Hip Flexion Fatigue On Over Ground Walking, Megan M. Rybar, Eric R. Walker, Henry Kuhnen, Daniel R. Ouellette, Reivian Berrios, Sandra K. Hunter, Allison Hyngstrom

Exercise Science Faculty Research and Publications

Individuals post stroke often rely more on hip flexors for limb advancement during walking due to distal weakness but the effects of muscle fatigue in this group is not known. The purpose of this study was to quantify how stroke affects the influence of hip flexor fatigue on over ground walking kinematics and performance and muscle activation. Ten individuals with chronic stroke and 10 without stroke (controls) participated in the study. Maximal walking speed, walking distance, muscle electromyograms (EMG), and lower extremity joint kinematics were compared before and after dynamic, submaximal fatiguing contractions of the hip flexors (30% maximal load) …


Sex Differences In Human Fatigability: Mechanisms And Insight To Physiological Responses, Sandra K. Hunter Apr 2014

Sex Differences In Human Fatigability: Mechanisms And Insight To Physiological Responses, Sandra K. Hunter

Exercise Science Faculty Research and Publications

Sex-related differences in physiology and anatomy are responsible for profound differences in neuromuscular performance and fatigability between men and women. Women are usually less fatigable than men for similar intensity isometric fatiguing contractions. This sex difference in fatigability, however, is task specific because different neuromuscular sites will be stressed when the requirements of the task are altered, and the stress on these sites can differ for men and women. Task variables that can alter the sex difference in fatigability include the type, intensity and speed of contraction, the muscle group assessed and the environmental conditions. Physiological mechanisms that are responsible …


Fatigability And Recovery Of Arm Muscles With Advanced Age For Dynamic And Isometric Contractions, Tejin Yoon, Bonnie Schlinder-Delap, Sandra K. Hunter Feb 2013

Fatigability And Recovery Of Arm Muscles With Advanced Age For Dynamic And Isometric Contractions, Tejin Yoon, Bonnie Schlinder-Delap, Sandra K. Hunter

Exercise Science Faculty Research and Publications

This study determined whether age-related mechanisms can increase fatigue of arm muscles during maximal velocity dynamic contractions, as it occurs in the lower limb. We compared elbow flexor fatigue of young (n = 10, 20.8 ± 2.7 years) and old men (n = 16, 73.8 ± 6.1 years) during and in recovery from a dynamic and an isometric postural fatiguing task. Each task was maintained until failure while supporting a load equivalent to 20% of maximal voluntary isometric contraction (MVIC) torque. Transcranial magnetic stimulation (TMS) was used to assess supraspinal fatigue (superimposed twitch, SIT) and muscle relaxation. Time …


Sex Differences In Marathon Running With Advanced Age: Physiology Or Participation?, Sandra K. Hunter, Alyssa A. Stevens Jan 2013

Sex Differences In Marathon Running With Advanced Age: Physiology Or Participation?, Sandra K. Hunter, Alyssa A. Stevens

Exercise Science Faculty Research and Publications

The sex difference in marathon performance increases with age and place of the finisher, even at the elite level. Sociological factors may explain the increased sex gap, but there is limited empirical evidence for specific factors.

Purpose: The purposes of this study were to determine the sex difference in velocity for the marathon across the place of finisher (1st–10th place) with advanced age and (2) to determine the association between the sex difference in participation (ratio of men-to-women finishers) and the sex difference in running velocity.

Methods: Running times of the first 10 placed men and women in the 5-yr …


Functional Implications Of Impaired Control Of Submaximal Hip Flexion Following Stroke, Allison S. Hyngstrom, Sandra K. Hunter Jan 2013

Functional Implications Of Impaired Control Of Submaximal Hip Flexion Following Stroke, Allison S. Hyngstrom, Sandra K. Hunter

Exercise Science Faculty Research and Publications

Introduction: We quantified sub-maximal torque regulation during low to moderate intensity isometric hip flexion contractions in individuals with stroke and the associations with leg function. Methods: 10 participants with chronic stroke and 10 controls performed isometric hip flexion contractions at 5%, 10%, 15%, 20%, and 40% of maximal voluntary contraction (MVC) in paretic, non-paretic, and control legs. Results: Participants with stroke had larger torque fluctuations (coefficient of variation, CV), for both the paretic and non-paretic legs, than controls (Pr2 =0.45) and Berg Balance Score (r2=0.38). At 5% MVC, there were larger torque fluctuations in the …


Electromyographical Analysis Of Lower Extremity Muscle Activation During Variations Of The Loaded Step-Up Exercise, Christopher J. Simenz, Luke Garceau, Brittney Lutsch, Timothy J. Suchomel, William P. Ebben Dec 2012

Electromyographical Analysis Of Lower Extremity Muscle Activation During Variations Of The Loaded Step-Up Exercise, Christopher J. Simenz, Luke Garceau, Brittney Lutsch, Timothy J. Suchomel, William P. Ebben

Exercise Science Faculty Research and Publications

The loaded step-up exercise allows strength and conditioning practitioners to incorporate a unilateral resistance for athletes while performing extension at the hip, knee, and plantar flexion at the ankle. This study evaluated the activation of the biceps femoris (BF), gluteus maximus (GMx), gluteus medius (GMe), rectus femoris, semitendinosus (ST), vastus lateralis, and vastus medialis during 4 variations of the step-up exercise to assess the specific muscle training stimulus of each exercise variation. The exercises included the step-up, crossover step-up, diagonal step-up, and lateral step-up. Fifteen women who regularly engaged in lower body resistance training performed the 4 exercises with 6 …


Weightlifting Performance Is Related To Kinematic And Kinetic Patterns Of The Hip And Knee Joints, Kristof Kipp, Josh Redden, Michelle B. Sabick, Chad Harris Jul 2012

Weightlifting Performance Is Related To Kinematic And Kinetic Patterns Of The Hip And Knee Joints, Kristof Kipp, Josh Redden, Michelle B. Sabick, Chad Harris

Exercise Science Faculty Research and Publications

The purpose of this study was to investigate the correlations between biomechanical outcome measures and weightlifting performance. Joint kinematics and kinetics of the hip, knee, and ankle were calculated while 10 subjects performed a clean at 85% of 1 repetition maximum (1RM). Kinematic and kinetic time-series patterns were extracted with principal components analysis. Discrete scores for each time-series pattern were calculated and used to determine how each pattern was related to body mass–normalized 1RM. Two hip kinematic and 2 knee kinetic patterns were significantly correlated with relative 1RM. The kinematic patterns captured hip and trunk motions during the first pull …


Supraspinal Fatigue Impedes Recovery From A Low-Intensity Sustained Contraction In Old Adults, Tejin Yoon, Bonnie Schlinder-Delap, Manda L. Keller, Sandra K. Hunter Mar 2012

Supraspinal Fatigue Impedes Recovery From A Low-Intensity Sustained Contraction In Old Adults, Tejin Yoon, Bonnie Schlinder-Delap, Manda L. Keller, Sandra K. Hunter

Exercise Science Faculty Research and Publications

This study determined the contribution of supraspinal fatigue and contractile properties to the age difference in neuromuscular fatigue during and recovery from a low-intensity sustained contraction. Cortical stimulation was used to evoke measures of voluntary activation and muscle relaxation during and after a contraction sustained at 20% of maximal voluntary contraction (MVC) until task failure with elbow flexor muscles in 14 young adults (20.9 ± 3.6 yr, 7 men) and 14 old adults (71.6 ± 5.4 yr, 7 men). Old adults exhibited a longer time to task failure than the young adults (23.8 ± 9.0 vs. 11.5 ± 3.9 min, …


Pain Perception After Isometric Exercise In Women With Fibromyalgia, Marie K. Hoeger Bement, Andy Weyer, Sarah Hartley, Breanna Drewek, April Harkins, Sandra K. Hunter Jan 2011

Pain Perception After Isometric Exercise In Women With Fibromyalgia, Marie K. Hoeger Bement, Andy Weyer, Sarah Hartley, Breanna Drewek, April Harkins, Sandra K. Hunter

Exercise Science Faculty Research and Publications

Objective: The purpose of this study was to identify exercise protocols incorporating isometric contractions that provide pain relief in women with fibromyalgia.

Design: A before-after trial.

Setting: A physical therapy department in an academic setting.

Participants: Fifteen women (mean ± SD, 52 ± 11y) with fibromyalgia.

Interventions: Subjects completed 4 sessions: 1 familiarization and 3 experimental. The following randomized experimental sessions involved the performance of isometric contractions with the elbow flexor muscles that varied in intensity and duration: (1) 3 maximal voluntary contractions (MVCs), (2) 25% MVC held to task failure, and (3) 25% MVC …