Rehabilitation and Therapy Commons^™

Stroke Increases Motor Output Variability During Maximal Voluntary Isometric Contractions Of Knee Extensor Muscles In Adults, Zhilun Zhou, Stephanie Christine Wolfe, Brian Schmit, Matthew J. Durand, Sandra Hunter, Allison Hyngstrom

Physical Therapy Faculty Research and Publications

Greater motor output variability (MOV, inconsistency and unsteadiness) during submaximal tasks post stroke is associated with poorer motor performance. However, little is known about MOV during maximal tasks and relationships with clinical measures of motor performance among stroke survivors. This study determined inconsistency (across discrete attempts) and unsteadiness (within a single attempt) during knee extension maximal voluntary isometric contractions (MVICs) in stroke survivors and neurotypical controls. Forty-three stroke survivors (28 female) and 31 age-matched neurotypical controls (15 female) performed a minimum of five knee extension MVICs with paretic and non-paretic legs (stroke) or dominant leg (controls). Inconsistency was calculated as …

Transitioning To Life After Sport: Empowering Former College Varsity Athletes To Live More Healthfully, Linda Piacentine, Taylor L. Wolf, Jacob J. Capin

Physical Therapy Faculty Research and Publications

Introduction: 

The transition out of competitive sport comes with a range of psychosocial challenges for athletes, particularly when retirement is involuntary (e.g., due to injury). Little is known about the health of former athletes who often manage prior injuries and changing biopsychosocial factors.

Purpose: 

Identify the unique experiences of varsity athletes during college and as they transition to life after college sports and determine the facilitators, barriers, and needs of college varsity athletes to engage in a physically active and healthy lifestyle after competitive sport retirement.

Methods: 

Thirty former college varsity athletes (15F, 15M; mean age 23 ± 1 yrs; …

Intermittent Phrenic Afferent Activation Induces Phrenic Motor Plasticity, Nicole M. Popp, Taylor C. Holmes, Elizabeth A. Rozycki, Kristi A. Streeter

Physical Therapy Faculty Research and Publications

Approaches such as electrical stimulation of the phrenic neuromuscular system are currently used in humans to manage breathing impairments. We recently showed that electrical stimulation of the diaphragm muscle induces phrenic afferent-dependent plasticity. These findings highlight the need to better understand the mechanisms of afferent-mediated plasticity to guide and improve the development of novel therapies using electrical stimulation. Here, we tested the hypothesis that intermittent activation of large-diameter phrenic afferents induces phrenic motor plasticity, which, like other forms of plasticity, is pattern sensitive. We delivered inspiratory-triggered electrical stimulation using a narrow pulse width (0.1 ms) to preferentially activate large-diameter afferents, …

Sport Training Day Affects Adolescent Athletes’ Sleep Schedules, Abigail Larson, Jena Heck Street, Roman De Guia, Jacob J. Capin

Physical Therapy Faculty Research and Publications

Introduction: Sufficient sleep is integral to overall health whereas suboptimal sleep puts athletes at greater risk for injury, lengthens their recovery time, and decreases their performance. Our purpose was to compare sleep across training days (i.e., competition, practice, and rest) in adolescent athletes, specifically identifying differences between nights before and after training.

Methods: Participants [n = 33 (14 male, 19 female), aged 15.6 ± 1.0 years] wore an activPAL accelerometer continuously for 14 consecutive days and completed a sleep log noting training day status (i.e., competition, practice, rest).

Results: Athletes slept less on the day after competition compared to …

Energy Flow Differences In Throwing Arm Joints Between Javelin And Weighted Balls In Male Javelin Throwers, Hans-Peter Köhler, Kristof Kipp, Nikola Prvulović, Maren Witt

Exercise Science Faculty Research and Publications

Introduction: To enhance release velocity during competition, javelin throwers incorporate implements of varying mass into their training regimens. Previous research has demonstrated that, although velocity contributes quadratically to the computation of kinetic energy, heavier implements generate substantially greater kinetic energy at the moment of release, despite markedly lower release velocities. The primary objective of the present investigation was to analyze energy transfer within the throwing arm to gain deeper insight into the biomechanical mechanisms underlying the use of implements with different masses.

Methods: The three-dimensional coordinates of 16 reflective markers were recorded for 6 athletes during throws using 6 different …

Improving Dynamic Balance And Gait Adaptation With Ischemic Conditioning Post-Stroke, Stephanie Christine Wolfe

Dissertations (1934 -)

The purpose of this dissertation was to quantify the benefits of ischemic conditioning on reactive balance responses and gait adaptation during treadmill walking in chronic stroke survivors. Reactive balance and gait adaptations are believed to be limited in this population. Ischemic conditioning is an emerging adjunct to physical therapy that improves motor function post-stroke via improvements in strength, voluntary muscle activation, walking speed, and fatigability. Here, we quantified how ischemic conditioning could impact performance of a more complex task: altering gait to meet various perturbing conditions. Specifically, we quantified mediolateral margin of stability in response to lateral cable pulls (both …

Mechanisms For The Age-Related Increase In Fatigability Of The Elbow Flexor Muscles In Healthy Adults, Blaine E. Arney, Andrew Kuplic, Mitchell D. Adam, Christopher W. Sundberg, Sandra Hunter

Exercise Science Faculty Research and Publications

The mechanisms for the age-related increase in fatigability of the elbow flexor muscles during dynamic contractions are unknown. The purpose of this study was to determine the contribution of supraspinal and contractile mechanisms for the age-related increase in fatigability of the elbow flexor muscles. Twenty-eight young (23.2 ± 2.6 years; 14 females) and 32 older adults (72.6 ± 5.6 years; 15 females) performed 80 maximal velocity contractions at 20% of maximal isometric strength. Voluntary activation and muscle contractile properties were assessed before and immediately following the fatiguing exercise using transcranial magnetic stimulation (TMS) and electrical stimulation. Fatigability (% reduction in …

Sex-Based Differences In The Representation Of Top Youth Athletes, Jessica J. James, Sandra K. Hunter, Elizabeth P. Bueckers, Michael J. Joyner, Jonathon W. Senefeld

Exercise Science Faculty Research and Publications

Although emerging research demonstrates that male athletes outperform female athletes before puberty, the effect of these sex-related advantages on ordinal ranking of top performances remains unclear.

Objectives

Among overall top performances of youth track and swimming athletes, we aimed to determine 1) the proportional number of male compared with female athletes represented and 2) at what age females are no longer represented.

Methods

Finishing times and sex of the top 10 and top 100 performances of youth runners and swimmers between 5 and 18 yr were abstracted from online U.S.-based databases for four running (100 m–800 m) and six freestyle …

Sex Differences In Motor Unit Behavior In Patients With Parkinson's Disease, Yuichi Nishikawa, Kohei Watanabe, Aleš Holobar, Tetsuya Takahashi, Noriaki Maeda, Hirofumi Maruyama, Allison Hyngstrom

Physical Therapy Faculty Research and Publications

The aim of this study was to determine whether there are sex differences in motor unit firing behavior in patients with Parkinson's disease. Twenty-seven patients with Parkinson's disease (females = 14 [age = 71.1 ± 6.8], males = 13 [age = 69.2 ± 10.3], Unified Parkinson's Disease Rating Scale Part III score; females = 10.8 ± 4.8, males = 11.4 ± 1.4) performed a contraction at 30% of the maximal voluntary contraction. For each participant, motor unit spike trains were decomposed from high-density surface electromyography data recorded from bilateral vastus lateralis muscles via blind source separation algorithms. In addition to …

Covid-19 And The Impact Of Physical Activity On Persistent Symptoms, Lauren E. Opielinski, Toni D. Uhrich, Michael H. Haischer, Rachel N. Beilfuss, Lindsey M. Mirkes Clark, Kamryn M. Kroner, Rachel E. Bollaert, Michael J. Danduran, Linda B. Piacentine, Marie K. Hoeger Bement, Paula E. Papanek, Sandra K. Hunter, Sarah J. Hamilton

Physical Therapy Faculty Research and Publications

Introduction: Physical activity is protective against chronic disease but whether activity is associated with persistent symptoms in non-hospitalized coronavirus disease 2019 (COVID-19) survivors is unknown. The purpose of the study was to determine the impact of the COVID-19 pandemic on physical activity levels and the influence of physical activity on acute COVID-19 and long COVID symptoms in non-hospitalized COVID-19 survivors.

Methods: In total, 64 non-hospitalized COVID-19 survivors (45 female participants, 40 ± 18 years) were assessed for activity levels, body composition, and symptoms of COVID-19 8.5 ± 4.7 months post-infection and categorized into two groups: (1) persistent symptoms and (2) …

Walking Performance Is Worse In Black Than White People With Multiple Sclerosis, Robert W. Motl, Deborah Backus, Jeffrey R. Hebert, Alexander V. Ng, Kevin K. Mccully, Whitney N. Neal, Hollie Schmidt, Robert Mcburney, Prudence Plummer, Francois Bethoux, John Lowman, Gary R. Cutter

Exercise Science Faculty Research and Publications

Background

There is emerging evidence for poor health outcomes among Black people with MS, and Black people with MS may have worse walking performance than White counterparts.

Purpose

The current study examined if Black participants with MS had slower walking speed (timed 25-foot walk, T25FW) and shorter walking distance (six-minute walk, 6MW) than White participants, and if these differences were accounted for by demographic variables, physical activity, disease/clinical characteristics, and Social Determinants of Health (SDOH).

Method

The analysis included samples of Black (N = 105) and White (N = 246) participants with MS who completed the T25FW and 6MW, underwent …

Treatment Of Osteoporosis And Osteoarthritis In The Oldest Old, Daniel Pinto

Physical Therapy Faculty Research and Publications

Osteoporosis and osteoarthritis are key diseases of musculoskeletal ageing and are increasing in prevalence and burden with the progressively ageing population worldwide. These conditions are thus particularly common in ‘the oldest old’, and there are complexities of managing them within the context of extensive multimorbidity, physical and mental disability, and polypharmacy, the rates for all of which are high in this population. In this narrative review, we explore the epidemiology of osteoporosis and osteoarthritis in the oldest old before examining trials and real-world data relating to the pharmacological treatment of these diseases in older adults, including anti-resorptives and bone-forming agents …

Pain Is Modulated Differently Between Females With And Without Patellofemoral Pain: Factors Related To Sensitization, Kemery J. Sigmund, Marie K. Hoeger Bement, Wendy E. Huddleston, Kyle T. Ebersole, Jennifer E. Earl-Boehm

Physical Therapy Faculty Research and Publications

Context

Patellofemoral pain (PFP) has poor long-term recovery outcomes. Central sensitization describes central nervous system changes altering pain modulation, which can complicate recovery (poorer prognosis and worse function). Signs of central sensitization include amplified pain facilitation, pain hypersensitivity, and impaired pain inhibition, which can be measured with temporal summation of pain (TSP), pressure pain thresholds (PPTs), and conditioned pain modulation (CPM), respectively. Sex differences exist for these test responses, but female-only PFP investigations of sensitization are uncommon. Understanding pain modulation in females with PFP could improve treatment protocols.

Objective

To determine whether females with PFP exhibit signs of central sensitization …

A Simple, Low-Cost Implant For Reliable Diaphragm Emg Recordings In Awake, Behaving Rats, Taylor C. Holmes, Jesus D. Penaloza-Aponte, Alyssa R. Mickle, Rachel L. Nosacka, Erica A. Dale, Kristi A. Streeter

Physical Therapy Faculty Research and Publications

Breathing is a complex neuromuscular process vital to sustain life. In preclinical animal models, the study of respiratory motor control is primarily accomplished through neurophysiologic recordings and functional measurements of respiratory output. Neurophysiologic recordings that target neural or muscular output via direct nerve recordings or respiratory muscle electromyography (EMG) are commonly collected during anesthetized conditions. While offering tight control of experimental preparations, the use of anesthesia results in respiratory depression, may impact cardiovascular control, eliminates the potential to record volitional nonventilatory behaviors, and can limit translation. Since the diaphragm is a unique muscle which is rhythmically active and difficult to …

Beliefs Regarding The Use Of Imaging Among Patients With Low Back Pain: A Cross-Sectional Study In The Context Of A Middle-Income Country, Leandro M. Diniz, Ítalo R. Lemes, Ana P. C. F. Freire, Ana F. Guimarães, Lucas A. C. Ferreira, Marcia R. Franco, Arianne P. Verhagen, Guy Simoneau, Rafael Z. Pinto

Physical Therapy Faculty Research and Publications

Introduction: Patients with low back pain may play an active role in the pre-scription of excessive spine imaging.

Objective: To determine the proportion of patients with low back pain who have beliefs not aligned with current evidence regarding the use of imaging and to identify factors associated with these beliefs.

Design: Secondary analysis of baseline data of a previously published randomized clinical trial.

Setting: Outpatient physical therapy clinic in a middle-income country.

Patients: Individuals with non-specific low back pain.

Methods: Outcome variables were two statements assessing the extent of patient agreement on the need for imaging in the management of …

Effects Of Ischemic Conditioning On Microvascular Reactivity To Single Passive Limb Movement In Young Adults: A Pilot Study, Alicen A. Whitaker-Hilbig, Jennifer N. Nguyen, Amanda E. Wietrzny, Gabriel R. Merkow, Sergey Tarima, Emilie A. Klevenow, Luke Nelson, Allison S. Hyngstrom, Matthew J. Durand

Physical Therapy Faculty Research and Publications

Purpose

Single passive limb movement (sPLM) of the lower extremity is a simple and clinically relevant measure of the microvascular vasodilatory response to movement. A promising stimulus to improve microvascular health is ischemic conditioning (IC). We examined whether a single session of IC could improve microvascular reactivity to sPLM in young adults.

Methods

This was a blinded, crossover, randomized clinical trial. Participants were seated in an isokinetic dynamometer that passively moved the knee 90° at a frequency of 1 Hz while superficial femoral artery leg blood flow (LBF) was measured. The absolute and the relative peak changes in LBF were …

Gamified Mhealth System For Evaluating Upper Limb Motor Performance In Children: Cross-Sectional Feasibility Study, Md Raihan Mia, Sheikh Iqbal Ahamed, Samuel Nemanich

Computer Science Faculty Research and Publications

Background: Approximately 17% of children in the United States have been diagnosed with a developmental or neurological disorder that affects upper limb (UL) movements needed for completing activities of daily living. Gold-standard laboratory assessments of the UL are objective and precise but may not be portable, while clinical assessments can be time-intensive. We developed MoEvGame, a mobile health (mHealth) gamification software system for the iPad, as a potential advanced technology to assess UL motor functions.

Objective: This feasibility study examines whether MoEvGame can assess children’s whole-limb movement, fine motor skills, manual dexterity, and bimanual coordination. The specific aims were to …

Prediction Of Snatch And Clean And Jerk Performance From Physical Performance Measures In Elite Male Weightlifters, Ingo Sandau, Kristof Kipp

Exercise Science Faculty Research and Publications

This study aimed to build a valid model to predict maximal weightlifting competition performance using ordinary least squares linear regression (OLR) and penalized (Ridge) linear regression (penLR) in 29 elite male weightlifters. One repetition maximum (1RM) or 3RM test results of assistant exercises were used as predictors. Maximal performance data of competition and assistant exercises were collected during a macrocycle in preparation for a competition. One repetition maximum snatch pull, 3RM back squat, 1RM overhead press, and body mass were used to predict the 1RM snatch; and 1RM clean pull, 3RM front squat, 1RM overhead press, and body mass were …

Perspectives Of Midwives And Nurse Practitioners In Kentucky On Exercise Counseling During Pregnancy: A Qualitative Study, Madhawa Perera, Taniya S. Nagpal, Maire M. Blankenship, Dano Tolusso, Jordyn Cox, Dilini Prashadika, Mark Schafer, Rachel A. Tinius

Physical Therapy Faculty Research and Publications

Introduction

Healthcare professionals are in an optimal position to deliver exercise information to pregnant women, yet previous research suggests this seldom happens. Midwives and nurse practitioners, who may have more time with pregnant women, are particularly well suited for this role.

Objectives

This qualitative study examined the exercise advice and counseling provided by midwives and nurse practitioners in Kentucky, focusing on the barriers they face.

Methods

Twenty-one midwives and nurse practitioners were recruited until the sample size reached saturation. A survey with open-ended questions was distributed to potential participants in regional hospitals, universities, and professional associations. The framework method was …

Rebuttal: Reduced Oxidative Capacity Of Skeletal Muscle Is Not An Inevitable Consequence Of Adult Ageing, Ian R. Lanza, Christopher W. Sundberg, Jane A. Kent

Physical Therapy Faculty Research and Publications

We thank Drs Marcinek and Ferrucci for their perspective on the inevitability of age-related declines in skeletal muscle oxidative capacity (Marcinek & Ferrucci, 2025). We agree that mitochondria have numerous roles in the cell beyond provision of chemical energy, many of which may be altered by ageing, but our focus in this debate is entirely on its role in energy production.

Effect Of Trauma Type And Trauma Burden On Self-Efficacy For Physical Exercise In Military Veterans, Kaley E. Davis, Meghan M. Bennett, Cecilia J. Hillard, Jeffrey Whittle, Zeno Franco, Rachel E. Bollaert, Jacklynn M. Fitzgerald

Exercise Science Faculty Research and Publications

Introduction

United States (U.S.) military veterans experience significant physical health problems. Lifestyle modifications, such as increasing daily physical activity, are often considered the first course of action in treatment for the general public. However, veterans report low levels of physical activity, often due to perceived barriers to engaging in exercise. Trauma exposure type and cumulative trauma burden may be differentially associated with exercise attitudes and behaviors.

Methods

We surveyed U.S. military veterans on perceived self-efficacy to overcome barriers to engaging in exercise and physical activity levels. Additionally, we explored the relationship between the type of traumatic event exposure and cumulative …

Whole Body Angular Momentum Characterizes Reactive Balance Adaptations And Perturbation Intensity, Mitchell D. Adam, Delaney Mcelvain, T. George Hornby, Allison S. Hyngstrom, Brian D. Schmit

Physical Therapy Faculty Research and Publications

Identifying measures which accurately quantify reactive balance adaptation during walking is essential to understand how emerging perturbation-based gait paradigms impact stability over the course of an intervention. These perturbation paradigms have shown promise in reducing falls for numerous clinical populations, however tracking progress in objective terms throughout an intervention remains challenging. Whole body angular momentum (H) may be particularly suited to detect subtle adaptations in the reactive balance response and is applicable within numerous perturbation environments. We assessed the ability of young healthy adults to adapt to varying intensities of discrete, unexpected, treadmill-based perturbations directed mediolaterally, anteriorly, and posteriorly during …

Age-Related Differences In Eye Movements And The Association With Archimedes Spiral Tracing Performance In Young And Older Adults, Brittany Heintz Walters, Wendy E. Huddleston, Kristian M. O'Connor, Jinsung Wang, Marie K. Hoeger Bement, Kevin G. Keenan

Physical Therapy Faculty Research and Publications

Age-related hand motor impairments may critically depend on visual information though few studies have examined eye movements during tasks of hand function in older adults. The purpose of this study was to assess eye movements and their association with performance while tracing on a touchscreen in young and older adults. Eye movements of 21 young (age 20–38 years; 12 females, 9 males) and 20 older (65–85 years; 10 females, 10 males) adults were recorded while performing an Archimedes spiral tracing task, a common clinical assessment sensitive to age-associated impairments in hand function. Participants traced an Archimedes spiral template on a …

Age-Related Differences In Behavioral Outcomes Of Bimanual Functional Motor Tasks In Children And Adolescents With Cerebral Palsy: A Scoping Review, Hubert D. Gascon, Sahian Alicia Maldonado Numata, Sandrine Emond, Samuel Nemanich, Maxime T. Robert

Occupational Therapy Faculty Research and Publications

Aim: The objective of this review is to determine age-related differences in behavioral outcomes of bimanual motor tasks in children and adolescents with cerebral palsy (CP). Method: This review followed the 6-stage Joanna Briggs institute methodology. The embase, EBSCO CINAHL, and PubMed databases were searched on May 2024. we included studies that employed instrumented measures to assess bimanual tasks in individuals with CP aged between 3 and 19 years.Results: Twenty-eight studies were included after full-text screening. This review reported on 544individuals with CP. Bimanual tasks were grouped in seven categories and their varying complexities were listed and analyzed. There are …

Blinding Of Transcranial Direct Current Stimulation Is Compromised In Typically Developing Children Compared To Young Adults, Sophia Bertrand, Tonya Rich, Samuel Nemanich

Occupational Therapy Faculty Research and Publications

Achieving successful blinding is a persistent challenge for clinical trials involving transcranial direct current stimulation. Studies involving populations with increased sensory sensitivity, such as children, could be at risk for increased bias from inadequate blinding due to unique sensation of stimulation relative to adults. The objectives of this study were 1) To examine differences in transcranial stimulation blinding between children and young adults and its relationship to sensory sensitivity. 2) To test the efficacy of an ActiSham protocol for participant blinding, compared to a traditional sham protocol. Typically developing right-handed children (N = 12, 5–14 yr) and young adults (N …

Relative Muscular Effort In The Older Adults During The Sit-To-Stand Task: Monitoring Neuromuscular Reserve And Movement Limitations, Nayun Ahn, Michael H. Haischer, Cara L. Lewis, Kristof Kipp

Exercise Science Faculty Research and Publications

Background

Due to lower maximum strength, older adults purportedly need to exert greater muscular effort to stand up from a chair. This study investigated joint-specific muscular effort during a sit-to-stand by calculating relative-muscular-effort and investigating differences between healthy older and young adults.

Methods

Fifteen older (age: 69.9 ± 3.5 years) and 15 young (age: 22.2 ± 2.6 years) adults performed five self-paced sit-to-stand trials. Kinematic and kinetic data were collected and used to calculate inverse dynamics net joint moment. Peak isometric knee and hip extensor torques were measured and used as inputs to regression models that predicted angle- and velocity-dependent …

Immediate Effect Of Local Vibration On Motor Unit Firing Behavior And Muscle Strength In Healthy Young Adult Males, Yuichi Nishikawa, Aleš Holobar, Kohei Watanabe, Toshihiko Komatsuzaki, Takanori Chihara, Jiro Sakamoto, Takashi Kawagoe, Hidetaka Nagayasu, Kyoko Mori, Kenji Kawano, Noriaki Maeda, Shinobu Tanaka, Allison S. Hyngstrom

Physical Therapy Faculty Research and Publications

Purpose

The aim of this study was to examine the effect of vibration on motor unit (MU) firing behavior and physical performance of antagonist muscles in healthy young adult males.

Methods

Fourteen males (age = 24.3 ± 3.6 years) were included in this study. There were two conditions, one in which participants received 80 Hz vibration in the distal tendon of the hamstring for 30 s and the control condition (no vibration). High-density surface electromyography (HD-SEMG) signals and maximal voluntary contraction (MVC) of knee extensor muscles were evaluated before and after the respective conditions and recorded from the vastus lateralis …

Oh, My Quad: A Clinical Commentary And Evidence-Based Framework For The Rehabilitation Of Quadriceps Size And Strength After Anterior Cruciate Ligament Reconstruction, Braidy Solie, Mitchell Carlson, Christopher Doney, Michael Kiely, Robert Laprade

Physical Therapy Faculty Research and Publications

Quadriceps weakness after anterior cruciate ligament reconstruction (ACLR) is a well-known phenomenon, with more persistent quadriceps weakness observed after ACLR with a bone-patellar tendon-bone or quadriceps tendon autograft than with a hamstring tendon autograft. Longstanding quadriceps weakness after ACLR has been associated with suboptimal postoperative outcomes and the progression of radiographic knee osteoarthritis, making the recovery of quadriceps size and strength a key component of ACLR rehabilitation. However, few articles have been written for the specific purpose of optimizing quadriceps size and strength after ACLR. Therefore, the purpose of this review article is to integrate the existing quadriceps muscle basic …

Performance Of Artificial Neural Network Compared To Multi-Linear Regression In Prediction Of Countermovement Jump Height, Amirhossein Emamian, Alireza Hashemi Oskouei, Kristof Kipp, Rasoul Azreh

Exercise Science Faculty Research and Publications

Previous research has used primarily linear regression models to predict jump height and establish contributors of performance. The purpose of this study was to compare the performance of artificial neural network (ANN) and multi-linear regression (MLR) in prediction of countermovement jump (CMJ) height and investigating the contribution of kinematic variables to CMJ performance. Thirty-four healthy young male athletes performed a total of 204 CMJ while eight kinematic variables (the hip, knee, and ankle angles at the begging of the concentric phase of CMJ, the hip and knee take-off angles, and the shoulder, hip, and knee maximum angular velocities) were used …

Neural And Muscular Contributions To The Age-Related Differences In Peak Power Of The Knee Extensors In Men And Women, David J. Wrucke, Andrew Kuplic, Mitchell D. Adam, Sandra K. Hunter, Christopher W. Sundberg

Physical Therapy Faculty Research and Publications

The mechanisms for the loss in limb muscle power output in old (60–79 yr) and very old (≥80 yr) adults and whether the mechanisms differ between men and women are not well understood. We compared maximal peak power of the knee extensor muscles between young, old, and very old men and women and identified the neural and muscular factors contributing to the age-related differences in power. Thirty-one young (22.9 ± 3.0 yr, 15 women), 82 old (70.3 ± 4.9 yr, 38 women), and 16 very old adults (85.8 ± 4.2 yr, 9 women) performed maximal isokinetic contractions at 14 different …