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Kinesiology

Walking

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Full-Text Articles in Life Sciences

Locomotor Sensory Organization Test: A Novel Paradigm For The Assessment Of Sensory Contributions In Gait, Jung Hung Chien, Diderik Jan Anthony Eikema, Mukul Mukherjee, Nicholas Stergiou Sep 2014

Locomotor Sensory Organization Test: A Novel Paradigm For The Assessment Of Sensory Contributions In Gait, Jung Hung Chien, Diderik Jan Anthony Eikema, Mukul Mukherjee, Nicholas Stergiou

Journal Articles

Feedback based balance control requires the integration of visual, proprioceptive and vestibular input to detect the body’s movement within the environment. When the accuracy of sensory signals is compromised, the system reorganizes the relative contributions through a process of sensory recalibration, for upright postural stability to be maintained. Whereas this process has been studied extensively in standing using the Sensory Organization Test (SOT), less is known about these processes in more dynamic tasks such as locomotion. In the present study, ten healthy young adults performed the six conditions of the traditional SOT to quantify standing postural control when exposed ...


A Comparative Evaluation Of The Effects Of Incline On Kinematics And Muscle Function During Backward Walking, Daniel Brent Jensen Aug 2014

A Comparative Evaluation Of The Effects Of Incline On Kinematics And Muscle Function During Backward Walking, Daniel Brent Jensen

UNLV Theses, Dissertations, Professional Papers, and Capstones

The purpose of this study was to investigate lower extremity kinematics and muscle activation patterns in inclined backward walking (IBW) versus traditional backward walking (BW). This purpose was achieved by evaluating performance of individuals walking backward on a treadmill at inclines of 0%, 6%, 8%, 10%, and 12%. Eleven participants (24.9 ± 4.8 yrs, 71.9 ± 11.6 kg, 1.7 ± 0.09m) recruited from the UNLV student body went through a familiarization training program before any data were collected. The familiarization training, which took place across 3 different days, served to: 1) help the participants become comfortable and ...


Adaptation And Prosthesis Effects On Stride-To-Stride Fluctuations In Amputee Gait, Shane R. Wurdeman, Sara A. Myers, Adam L. Jacobsen, Nicholas Stergiou Jun 2014

Adaptation And Prosthesis Effects On Stride-To-Stride Fluctuations In Amputee Gait, Shane R. Wurdeman, Sara A. Myers, Adam L. Jacobsen, Nicholas Stergiou

Journal Articles

Twenty-four individuals with transtibial amputation were recruited to a randomized, crossover design study to examine stride-to-stride fluctuations of lower limb joint flexion/extension time series using the largest Lyapunov exponent (λ). Each individual wore a “more appropriate” and a “less appropriate” prosthesis design based on the subject's previous functional classification for a three week adaptation period. Results showed decreased λ for the sound ankle compared to the prosthetic ankle (F1,23 = 13.897, p = 0.001) and a decreased λ for the “more appropriate” prosthesis (F1,23 = 4.849, p = 0.038). There was also a significant ...


Biomechanical Analysis Of Gait Kinetics Resulting From Use Of A Vacuum Socket On A Transtibial Prosthesis, Maria De Lourdes Ramos Gonzalez May 2014

Biomechanical Analysis Of Gait Kinetics Resulting From Use Of A Vacuum Socket On A Transtibial Prosthesis, Maria De Lourdes Ramos Gonzalez

Honors College Theses

The technology and design of lower limb prosthetics have evolved greatly since their introduction. The current study proposed to compare the effects of a conventional pin socket attachment and a vacuum socket attachment for a transtibial amputee. Whereas traditional measurements of gait utilize force plates and camera systems, this study made use of a small tri-axial load cell located at the base of the socket to measure the forces and moments exerted during a regular gait cycle. The hypothesis tested stated that a vacuum pump socket attachment, when compared to a non-vacuum (pin) socket, will have a significant effect on ...


Examining Mediators To Physical Activity As A Link To Interventional Efforts Aimed At Increasing Activity Levels And Improving Physical Functioning In Older Adults, Christopher Dondzila Aug 2013

Examining Mediators To Physical Activity As A Link To Interventional Efforts Aimed At Increasing Activity Levels And Improving Physical Functioning In Older Adults, Christopher Dondzila

Theses and Dissertations

The number of older adults living in the United States is growing at an increasingly rapid rate, and is host to a high prevalence of chronic diseases and physical impairments. Physical activity and exercise have been shown to be beneficial in impacting such conditions, yet the majority of older adults remain inactive. The purpose of this dissertation was to employ a sequence of studies to investigate mediators to physical activity, leading to an intervention to increase activity and promote health.

The purpose of Project VOICE was to examine whether awareness and utilization of community resources to promote physical activity and ...


Gait Variablility Is Altered In Older Adults When Listening To Auditory Stimuli With Differing Temporal Structures, Jeffrey P. Kaipust, Denise Mcgrath, Mukul Mukherjee, Nicholas Stergiou Aug 2013

Gait Variablility Is Altered In Older Adults When Listening To Auditory Stimuli With Differing Temporal Structures, Jeffrey P. Kaipust, Denise Mcgrath, Mukul Mukherjee, Nicholas Stergiou

Journal Articles

Gait variability in the context of a deterministic dynamical system may be quantified using nonlinear time series analyses that characterize the complexity of the system. Pathological gait exhibits altered gait variability. It can be either too periodic and predictable, or too random and disordered, as it is the case with aging. While gait therapies often focus on restoration of linear measures such as gait speed or stride length, we propose that the goal of gait therapy should be to restore optimal gait variability, which exhibits chaotic fluctuations and is the balance between predictability and complexity. In this context, our purpose ...


Measuring Activity Energy Expenditure: Accuracy Of The Gt3x+ And Actiheart Monitors, David Mcminn, Rijan Acharya, David A. Rowe, Stuart R. Gray, Julia L. Allan Jul 2013

Measuring Activity Energy Expenditure: Accuracy Of The Gt3x+ And Actiheart Monitors, David Mcminn, Rijan Acharya, David A. Rowe, Stuart R. Gray, Julia L. Allan

International Journal of Exercise Science

International Journal of Exercise Science 6(3) : 217-229, 2013. The purpose was to determine the accuracy of the GT3X+ and Actiheart monitors for estimating energy expenditure (EE) and steps. Additionally, to investigate agreement between waist- and wrist-mounted GT3X+ EE outputs. Nineteen participants (mean age=30) completed three treadmill walking trials at self-selected slow, medium, and fast speeds while wearing two GT3X+ (waist and wrist) and an Actiheart. Activity monitor EE was compared to indirect calorimetry criterion EE using Pearson correlations and ANOVAs. A Bland-Altman plot was used to investigate agreement between GT3X+ waist- and wrist-determined EE. GT3X+ determined steps were ...


Executive Function Orchestrates Regulation Of Task-Relevant Gait Fluctuations, Leslie M. Decker, Fabien Cignetti, Nicholas Stergiou Jul 2013

Executive Function Orchestrates Regulation Of Task-Relevant Gait Fluctuations, Leslie M. Decker, Fabien Cignetti, Nicholas Stergiou

Journal Articles

Humans apply a minimum intervention principle to regulate treadmill walking, rapidly correcting fluctuations in the task-relevant variable (step speed: SS) while ignoring fluctuations in the task-irrelevant variables (step time: ST; step length: SL). We examined whether the regulation of fluctuations in SS and not in ST and SL depends on high-level, executive function, processes. Young adults walked on a treadmill without a cognitive requirement and while performing the cognitive task of dichotic listening. SS fluctuations became less anti-persistent when performing dichotic listening, meaning that taxing executive function impaired the ability to rapidly correct speed deviations on subsequent steps. Conversely, performing ...


Biomechanical Comparison Of A Rounded Outsole Shoe And Traditional Outsole Shoe, Sarah Horsch May 2013

Biomechanical Comparison Of A Rounded Outsole Shoe And Traditional Outsole Shoe, Sarah Horsch

UNLV Theses, Dissertations, Professional Papers, and Capstones

The purpose of the study was to determine the effects of shoe outsole design on maximum vertical acceleration and select kinematic parameters during level and uphill walking across phases of stance. Twelve participants, 7 males (75.1±9.3 kg, 173.6±3.6 cm, 22.9±3.5 yrs) and 5 females (56.5±5.1 kg, 158.3±4.5 cm, 25.4±11.1 yrs) granted written consent and preferred walking speed was determined. An accelerometer (480 Hz) was attached to the distal leg to measure maximum leg acceleration (Aleg) and an electrogoniometer (480 Hz) was placed ...


Kinematic Effects Of Stride Length Perturbations On System Com Horizontal Velocity During Locomotion, Josh Bailey, Andrew Nordin, Janet Dufek, D. Lee Apr 2013

Kinematic Effects Of Stride Length Perturbations On System Com Horizontal Velocity During Locomotion, Josh Bailey, Andrew Nordin, Janet Dufek, D. Lee

Interdisciplinary Research Scholarship Day

PURPOSE: To investigate the kinematic effect on the systems’ center of mass horizontal velocity in response to stride length perturbations. METHODS: Twelve healthy adults (23.1±7.71 yrs; 1.69±0.1 m; 66.82±12.6 kg; leg length 894.7±66.1 mm) performed 5 trials of preferred speed walking (PW) and running (PR)followed by 5 stride length perturbations based on percentages of leg length (60%, 80%, 100%, 120% and 140%). 3D kinematic analysis was completed using a 12-camera infrared motion capture system (Vicon, 200hz). Dependent variables computer for each condition included: center of mass horizontal ...


Step Length Perturbations Alter Variations In Center Of Mass Horizontal Velocity, Josh Bailey, Andrew Nordin, D. Lee, Janet Dufek Apr 2013

Step Length Perturbations Alter Variations In Center Of Mass Horizontal Velocity, Josh Bailey, Andrew Nordin, D. Lee, Janet Dufek

Interdisciplinary Research Scholarship Day

PURPOSE: The purpose of the study was to investigate the effects of SL perturbations on system COM forward velocity (vx) during walking gait. METHODS: Eight healthy adults (23.5±3.6 yrs; 1.72±0.18 m; 73.11±15.29 kg) performed 5 trials of preferred speed walking (PW) and running (PR) followed by 5 stride length perturbations based on percentages of leg length (LL: 60%, 80%, 100%, 120% and 140%). 3D kinematic analysis was completed using a 12-camera infrared motion capture system (Vicon MX T40-S, 200Hz). Data filtering and interpolation included a low pass, 4th order Butterworth filter ...


Effects Of Shoe Outsole Design And Incline On Walking Biomechanics, Sarah Horsch, Janet Dufek Apr 2013

Effects Of Shoe Outsole Design And Incline On Walking Biomechanics, Sarah Horsch, Janet Dufek

Interdisciplinary Research Scholarship Day

The purpose of the study was to examine the effects of incline at foot contact of treadmill walking between rounded outsole (ROS) and traditional outsole (TOS) shoes. A rounded outsole shoe (ROS) is specifically designed with a fulcrum under the sole so that when the mass of the body is over it, the foot is forced to roll anteriorly. Traditional ROS studies have included analyses on bipedal stance single leg standing, muscle
activity during treadmill walking, kinetics during over ground walking, and kinematics after a 6-week accommodation period. Presently, there is no research comparing a ROS and a TOS at ...


Loading Of The Lower Extremity And Low Back When Using Wedge Orthotics During Walking And Stair Negotiation, Tami Janssen Jan 2013

Loading Of The Lower Extremity And Low Back When Using Wedge Orthotics During Walking And Stair Negotiation, Tami Janssen

Graduate Theses and Dissertations

ABSTRACT

Wedge orthotics are commonly prescribed for patients with hyperpronation and/or low back pain to improve lower limb alignment and to reduce pain. The purpose of this study was to examine the kinetic effects of medial and lateral wedge orthotics during walking and stair negotiation. Twenty-two healthy young adults participated in the study. Each participant wore no wedge (W0) as a baseline and lateral and medial wedge orthotics at 3 degrees and 7 degrees bilaterally (L3, L7, M3, M7) during walking, stair ascent, and stair descent. Ankle, knee, and hip joint moments were calculated using inverse dynamics during the ...


Can Sedentary Behavior Be Made More Active? A Randomized Pilot Study Of Tv Commercial Stepping Versus Walking, Jeremy A. Steeves, David R. Bassett, Eugene C. Fitzhugh, Hollie Raynor, Dixie L. Thompson Aug 2012

Can Sedentary Behavior Be Made More Active? A Randomized Pilot Study Of Tv Commercial Stepping Versus Walking, Jeremy A. Steeves, David R. Bassett, Eugene C. Fitzhugh, Hollie Raynor, Dixie L. Thompson

Kinesiology, Recreation, and Sport Studies Publications and Other Works

Background

There is a growing problem of physical inactivity in America, and approximately a quarter of the population report being completely sedentary during their leisure time. In the U.S., TV viewing is the most common leisure-time activity. Stepping in place during TV commercials (TV Commercial Stepping) could increase physical activity. The purpose of this study was to examine the feasibility of incorporating physical activity (PA) into a traditionally sedentary activity, by comparing TV Commercial Stepping during 90 min/d of TV programming to traditional exercise (Walking).

Methods

A randomized controlled pilot study of the impact of 6 months of ...


Sensitivity Of The Wolf’S And Rostein’S Algorithms To Evaluate Local Dynamic Stability From Small Gait Data Sets, Fabien Cignetti, Leslie M. Decker, Nicholas Stergiou May 2012

Sensitivity Of The Wolf’S And Rostein’S Algorithms To Evaluate Local Dynamic Stability From Small Gait Data Sets, Fabien Cignetti, Leslie M. Decker, Nicholas Stergiou

Journal Articles

The Wolf’s (W-algorithm) and Rosenstein’s (R-algorithm) algorithms have been used to quantify local dynamic stability (largest Lyapunov exponent, λ 1) in gait, with prevalence of the latter one that is considered more suitable for small data sets. However, such a claim has never been investigated. To address it, the λ 1 of the Lorenz attractor was estimated using small data sets and varied delays and embedding dimensions. Overall, the λ 1 estimates from the R-algorithm got closer to the theoretical exponent than those from the W-algorithm. The W-algorithm also overestimated λ 1 while ...


Comparative Analysis Of The Energy Expenditure In Walking And The Running In Young Men, Lucas De Castro Cardoso, Marcelo De Castro Cesar, Pamela Roberta Gomes Gonelli, Claudio Alexandre Gobatto Mar 2012

Comparative Analysis Of The Energy Expenditure In Walking And The Running In Young Men, Lucas De Castro Cardoso, Marcelo De Castro Cesar, Pamela Roberta Gomes Gonelli, Claudio Alexandre Gobatto

International Journal of Exercise Science: Conference Proceedings

Walking below 6 km/h and running above 8 km/h are efficient effort intensities to maintain the economy of energy expenditure in the mechanical work. However, in the intermediate range (between the transition of the walking to running), the mechanical work against the energy expenditure still requires analysis. So, the purpose of the present study was to compare the energy expenditure between walking and running in the load work immediately below of the inversion point in the caloric expenditure. Ten young male subjects participated of the study (24.2 ± 2.04 years; 180.7 ± 3.8 cm; 79.5 ...


Adaptations To Stride Patterns And Head Movements During Walking In Persons With And Without Multiple Sclerosis, Jebb Grigory Remelius Feb 2012

Adaptations To Stride Patterns And Head Movements During Walking In Persons With And Without Multiple Sclerosis, Jebb Grigory Remelius

Open Access Dissertations

Many people with multiple sclerosis (MS) have difficulty with walking, which can decrease their sense of mobility. Gait stability was investigated by studying stride parameters and head movements at preferred and fixed speeds in those with MS. First, walking gait data were recorded at preferred and fixed walking speeds from 19 individuals with MS and 19 controls. Traditional gait parameters were compared, as was swing foot to center of mass (CoM) timing at mid-swing. Second, walking gait data in healthy young adults (n=20) were recorded at preferred speed and while stepping over an obstacle. Study 2 developed novel swing ...


Frontal Joint Dynamics When Initiating Stair Ascent From A Walk Versus A Stand, Srikant Vallabhajosula, Jenna M. Yentes, Nicholas Stergiou Feb 2012

Frontal Joint Dynamics When Initiating Stair Ascent From A Walk Versus A Stand, Srikant Vallabhajosula, Jenna M. Yentes, Nicholas Stergiou

Journal Articles

Ascending stairs is a challenging activity of daily living for many populations. Frontal plane joint dynamics are critical to understand the mechanisms involved in stair ascension as they contribute to both propulsion and medio-lateral stability. However, previous research is limited to understanding these dynamics while initiating stair ascent from a stand. We investigated if initiating stair ascent from a walk with a comfortable self-selected speed could affect the frontal plane lower-extremity joint moments and powers as compared to initiating stair ascent from a stand and if this difference would exist at consecutive ipsilateral steps on the stairs. Kinematics data using ...


School Program Planning To Increase Active Transport To School, Brenda Aguilar Jan 2012

School Program Planning To Increase Active Transport To School, Brenda Aguilar

McNair Poster Presentations

Studies have shown that active transport is known to increase physical activity of children, decrease traffic congestion and the production of greenhouse gasses. This study examines active transport to school (ATS) [walking, biking, or other self-powered wheels to school] among elementary students. Through the Nevada Moves Day program an increase proportion of elementary students who use ATS was expected.

This study was done at two elementary schools, one being the intervention school that participated in the Nevada Moves Day, and a control school, which did not participate. Data was collected over a three week period. Students using active transport and ...


New Insights Into Anterior Cruciate Ligament Deficiency And Reconstruction Through The Assessment Of Knee Kinematic Variability In Terms Of Nonlinear Dynamics, Leslie M. Decker, Constantina O. Moraiti, Nicholas Stergiou, Anastasios D. Georgoulis Oct 2011

New Insights Into Anterior Cruciate Ligament Deficiency And Reconstruction Through The Assessment Of Knee Kinematic Variability In Terms Of Nonlinear Dynamics, Leslie M. Decker, Constantina O. Moraiti, Nicholas Stergiou, Anastasios D. Georgoulis

Journal Articles

Purpose

Injuries to the anterior cruciate ligament (ACL) occur frequently, particularly in young adult athletes, and represent the majority of the lesions of knee ligaments. Recent investigations suggest that the assessment of kinematic variability using measures of nonlinear dynamics can provide with important insights with respect to physiological and pathological states. The purpose of the present article was to critically review and synthesize the literature addressing ACL deficiency and reconstruction from a nonlinear dynamics standpoint.

Methods

A literature search was carried out in the main medical databases for studies published between 1990 and 2010.

Results

Seven studies investigated knee kinematic ...


Variability Of Vertical Ground Reaction Forces In Patients With Chronic Low Back Pain, Before And After Chiropractic Care., Brent S. Russell, Mark D. Geil, Jianhua Wu, Kathryn T. Hoiriis Aug 2011

Variability Of Vertical Ground Reaction Forces In Patients With Chronic Low Back Pain, Before And After Chiropractic Care., Brent S. Russell, Mark D. Geil, Jianhua Wu, Kathryn T. Hoiriis

Kinesiology Theses

Introduction

Many chiropractic articles and textbooks discuss gait, but there actually has been little research into the effects of chiropractic adjustment on gait. This pilot study used a quantitative method of gait evaluation before and after a series of chiropractic visits. Hypotheses: (1) adults with chronic low back pain (CLBP) would show increased variability in vertical ground reaction forces (VGRF) while walking, as compared to healthy control subjects, and (2) that, following chiropractic care, will show decreased variability.

Methods

VGRF data were collected for 6 controls and compared to 9 CLBP participants, who were also evaluated before and after the ...


Gait Variability Of Patients With Intermittent Claudication Is Similar Before And After The Onset Of Claudication Pain, Sara A. Myers, Iraklis Pipinos, Jason Johanning, Nicholas Stergiou Aug 2011

Gait Variability Of Patients With Intermittent Claudication Is Similar Before And After The Onset Of Claudication Pain, Sara A. Myers, Iraklis Pipinos, Jason Johanning, Nicholas Stergiou

Journal Articles

Background

Recent research demonstrated that intermittent claudication patients have increased gait variability prior to the onset of claudication. However, it is unknown if these patients experience additional gait adaptations after the onset of claudication. Thus, we sought to determine how gait variability is affected by claudication in an effort to contribute to improved clinical management.

Methods

Twenty-six intermittent claudication patients and 20 controls walked on a treadmill at self-selected speed; intermittent claudication patients were tested before (pain free) and after (pain) the onset of claudication. Variability of the ankle, knee, and hip joint angles was assessed using the largest Lyapunov ...


Can America’S Top Sedentary Activity Be Made More Active?: Physical Activity And Leisure-Time Study (Pals), Jeremy Adam Steeves May 2011

Can America’S Top Sedentary Activity Be Made More Active?: Physical Activity And Leisure-Time Study (Pals), Jeremy Adam Steeves

Doctoral Dissertations

This dissertation investigated 1) the energy expenditure of stepping in place during TV commercials (commercial stepping), 2) determined the best objective tool to measure commercial stepping, 3) and assessed the efficacy of commercial stepping to increase the activity levels of sedentary, overweight adults.
First, twenty-three adults (normal to obese) had their energy expenditure measured while at rest, sitting, standing, stepping in place and walking at 3.0 mph on the treadmill, followed by one hour each of sedentary TV viewing and commercial stepping in the laboratory. Stepping in place, walking at 3.0 mph, and commercial stepping, had a higher ...


Neuromuscular Responses Of The Vastus Lateralis To Slow Walking With Vascular Restriction., Robert Cardenas, Charity Cavazos, Jose A. Leal Jr., Yoshiaki Sato, Michael G. Bemben, Murat Karabulut Feb 2011

Neuromuscular Responses Of The Vastus Lateralis To Slow Walking With Vascular Restriction., Robert Cardenas, Charity Cavazos, Jose A. Leal Jr., Yoshiaki Sato, Michael G. Bemben, Murat Karabulut

International Journal of Exercise Science: Conference Proceedings

Motor unit recruitment of individual muscles could substantially differ with changes in speed and load. However, the recruitment patterns associated with low intensity walk training with vascular restriction at sustained loads and constant speed could be different than normal walking. Vascular restricted (VR) walk training is an effective method for increasing muscular strength; however the changes in motor unit recruitment and firing frequency have not been investigated to understand the mechanisms underlying the neuromuscular adaptations. Purpose: The purpose of this study was to analyze differences in electrical activity of the vastus lateralis during VR and non vascular restricted (non-VR) walking ...


A Comparison Of Hypertrophy Potential Between The Vastus Lateralis And Rectus Femoris During Level Walking In Combination With Vascular Restriction., Jose A. Leal Jr., Charity Cavazos, Robert Cardenas, Yoshiaki Sato, Bemben G. Michael, Murat Karabulut Feb 2011

A Comparison Of Hypertrophy Potential Between The Vastus Lateralis And Rectus Femoris During Level Walking In Combination With Vascular Restriction., Jose A. Leal Jr., Charity Cavazos, Robert Cardenas, Yoshiaki Sato, Bemben G. Michael, Murat Karabulut

International Journal of Exercise Science: Conference Proceedings

Recent research has found that by compressing blood flow to working muscle during lower body exercise involving short bouts of walk training results in an increased muscle volume and improved quadriceps strength. However, the effects of vascular restriction (VR) during walking on neuromuscular adaptations as assessed by electromyography (EMG) activity may provide insight on how low intensity training with vascular restriction can be applied to various modes of exercise. PURPOSE: The purpose of this study was to explore and compare muscle activation changes of the quadriceps muscles during walking using EMG with and without blood flow restriction. METHODS: EMG electrodes ...


A Comparison Of Commonly Used Accelerometer Based Activity Monitors In Controlled And Free-Living Environment, Yuri Feito Dec 2010

A Comparison Of Commonly Used Accelerometer Based Activity Monitors In Controlled And Free-Living Environment, Yuri Feito

Doctoral Dissertations

This dissertation was designed to determine the effects of body mass index (BMI) and walking speed on activity monitor outputs. A secondary purpose was to compare the activity monitors’ performance in a free-living environment. In the first experiment, 71 participants wore three waist-mounted activity monitors (Actical, ActiGraph, and NL-2000) and an ankle-mounted device (StepWatch 3) while walking on a treadmill (40, 67 and 94 m/min). The tilt angle of each device was measured. The Actical recorded 26% higher activity counts (P < 0.01) in obese persons with a tilt <10 degrees, compared to normal weight persons. The ActiGraph was unaffected by BMI or tilt angle. In the second experiment, the steps recorded by the devices were compared to actual steps. Speed had the greatest influence on the accuracy these devices. At 40 m/min, the ActiGraph was the least accurate device for normal weight (38%), overweight (46%) and obese (48%) individuals. The Actical, NL-2000 and StepWatch averaged 65%, 73% and 99% of steps taken, respectively. Lastly, several generations of the ActiGraph (7164, GT1M, and GT3X), and other research grade activity monitors (Actical; ActivPAL; and Digi-Walker) were compared to a criterion measure of steps. Fifty-six participants performed treadmill walking (40, 54, 67, 80 and 94 m/min) and wore the devices for 24-hours under free-living conditions. BMI did not affect step count accuracy during treadmill walking. The StepWatch, PAL, and the AG7164 were the most accurate across all speeds; the other devices were only accurate at the faster speeds. In the free-living environment, all devices recorded about 75% of StepWatch-determined steps, except the AG7164 (99%). Based on these findings, we conclude that BMI does not affect the output of these activity monitors. However, waist-borne activity monitors are highly susceptible to under-counting steps at walking speeds below 67 m/min, or stepping rates below 100 steps/min. An activity monitor worn on the ankle is less susceptible to these speed effects and provides the greatest accuracy for step counting.


Biomechanical Risk Factors For Knee Osteoarthritis In Young Adults: The Influence Of Obesity And Gait Instruction, Julia Ann Freedman Dec 2010

Biomechanical Risk Factors For Knee Osteoarthritis In Young Adults: The Influence Of Obesity And Gait Instruction, Julia Ann Freedman

Doctoral Dissertations

With increasing rates of obesity, research has begun to focus of co-morbidities of obesity such as osteoarthritis. The majority of existing research has focused on older adults as the group most likely to suffer from osteoarthritis. The purpose of this study was to determine if overweight and obese young adults exhibit biomechanical risk factors for knee osteoarthritis, and to determine if young adults with biomechanical risk factors of osteoarthritis can modify these with instruction. This purpose was divided into two separate studies.

Study 1: Thirty adults between 18-35 years old were recruited into three groups according to body mass index ...


A Comparison Of The Actigraph 7164 And The Actigraph Gt1m During Self-Paced Locomotion, Sarah Kozey, John Staudenmayer, Richard Troiano, Patty Freedson May 2010

A Comparison Of The Actigraph 7164 And The Actigraph Gt1m During Self-Paced Locomotion, Sarah Kozey, John Staudenmayer, Richard Troiano, Patty Freedson

Patty S. Freedson

Purpose—This study compared the ActiGraph accelerometer model 7164 (AM1) to the ActiGraph GT1M (AM2) during self-paced locomotion. Methods—Participants n = 116, 18–73y, mean BMI = 26.1) walked at self-selected slow, medium, and fast speeds around an indoor circular hallway (0.47km). Both activity monitors were attached to a belt secured to the hip and simultaneously collected data in 60 second epochs. To compare differences between monitors, the average difference (bias) in count output and steps output were computed at each speed. Time spent in different activity intensities (light, moderate, vigorous) based on the Freedson et al. cut-points was ...


Walking Class Step Average, Step Intensity, Distance Covered And Leisure Physical Activity Of College Students, Kimberly D. Tallent Mar 2010

Walking Class Step Average, Step Intensity, Distance Covered And Leisure Physical Activity Of College Students, Kimberly D. Tallent

International Journal of Exercise Science: Conference Proceedings

PURPOSE. The purpose of this study was to examine the relationship between stepping levels in and outside of a prescribed walking class and leisure time physical activity (PA) of college students. METHOD. Participants in the study were twenty three male (n = 9) and female (n = 14) enrolled in a walking class that met Monday through Friday for five weeks during the summer. Students completed the short version of the International Physical Activity Questionnaire (IPAQ) at the beginning and end of the course and followed the prescribed walking times during class. Step counts were ascertained both in and outside class and ...


Medial Longitudinal Arch Mechanics Before And After A Prolonged Run, Elizabeth Rose Hageman Jan 2010

Medial Longitudinal Arch Mechanics Before And After A Prolonged Run, Elizabeth Rose Hageman

Graduate Theses and Dissertations

Collapse and reformation of the medial longitudinal arch during gait is controlled passively and actively. If either tissue group fatigues over the duration of a run, the change in arch mechanics may increase risk of running injuries. However, a 3-dimensional kinematic analysis of the medial longitudinal arch after a prolonged run has not been performed. Additionally, rarely has arch collapse been quantified for walking and running in the same study. PURPOSE: To compare arch mechanics before and after a 45 minute run and to compare walking and running arch deformation. METHODS: Thirty runners performed barefoot walking and running trials before ...