Kinesiology Commons^™

Chapter 8: Autocorrelation Function, Mutual Information, And Correlation Dimension, Nathaniel Hunt

Journal Articles

In this chapter, we will discuss in greater detail the autocorrelation function and the mutual information we mentioned in Chapter 3 on the reconstruction of the state space. We will also cover a new measure called the correlation dimension, which quantifies the dimensionality of an attractor.

Chapter 5: Surrogation, Sara A. Myers

Journal Articles

One of the goals of time series analysis is to understand the underlying mechanisms that generate different dynamics for different time series. If a time series is not a product of random process, then we can assume that some kind of dynamics govern the time series. The question is what kinds of dynamics are controlling the time series. For nonlinear time series analysis, our focus is on nonlinear dynamics, and one of the goals is to characterize those dynamics by applying nonlinear tools. However, it is important to establish evidence of nonlinearity in a time series first in order to …

Chapter 2: Time Series, Sara A. Myers

Journal Articles

Time series is “simply a list of numbers assumed to measure some process sequentially in time” (Stergiou et al. 2004). Mathematicians have a more formal definition, that is, a set or a sequence of observations, with each one recorded at specific times, or at least sequentially (Brockwell and Davis 2002; Box et al. 2008). Time series are created from multiple sources for research purposes to understand various behaviors. For example, social scientists could collect graduation rates, physiologists record heart rates, economists study consumer spending, and climatologists examine weather patterns. Basically, any time observations are taken repeatedly over time, from any …

Impact Of Age On The Vasodilatory Function Of Human Skeletal Muscle Feed Arteries, Song-Young Park, S. J. Ives, J. R. Gifford, R. H. I. Andtbacka, John R. Hyngstrom, Van Reese, Gwenael Layec, Leena P. Bharath, J. David Symons, Russell S. Richardson

Health and Kinesiology Faculty Publications

Although advancing age is often associated with attenuated skeletal muscle blood flow and skeletal muscle feed arteries (SMFAs) have been recognized to play a regulatory role in the vasculature, little is known about the impact of age on the vasodilatory capacity of human SMFAs. Therefore, endothelium-dependent and -independent vasodilation were assessed in SMFAs (diameter: 544 ± 63 μm) obtained from 24 (equally represented) young (33 ± 2 yr) and old (71 ± 2 yr) subjects in response to three stimuli: 1) flow-induced shear stress, 2) ACh, and 3) sodium nitropusside (SNP). Both assessments of endothelium-dependent vasodilation, flow …

The Effect Of Cardiorespiratory Fitness On The Assessment Of The Physical Working Capacity At The Fatigue Threshold, Brittney M. Mikkelsen, Jorge Zuniga, William K. Herron, Frances E. Frauso, Anne N. Pulliam

Journal Articles

Purpose: The purpose of this study was to determine if different cardiorespiratory fitness levels (maximal oxygen uptake or VO2max) affect neuromuscular fatigue as measured by the physical working capacity at the fatigue threshold (PWCFT). Methods: Fourteen adults (14 men; mean ± SD; age = 20.79 ± 0.89 years; body weight = 80.7 ± 10.91 kg; height = 178.4 ± 5.29 cm) volunteered to participate in the investigation. Each participant performed an incremental cycle ergometry test to fatigue while electromyographic (EMG) signals were measured from the vastus lateralis (VL) muscle. Mean, standard deviation, and range values were calculated for …

Freezing Of Gait Associated With A Corpus Callosum Lesion, Marian L. Dale, Martina Mancini, Carolin Curtze, Fay B. Horak, Brett W. Fling

Journal Articles

Freezing of gait (FoG) is a debilitating feature of Parkinson’s disease and other parkinsonian disorders. This case demonstrates a variant of freezing of gait in a non-parkinsonian patient with a lesion of the anterior corpus callosum. The freezing improved with increased upper extremity sensory input, suggesting that compensatory circuits for use of somatosensory inputs from the arms to postural and locomotor centers were intact.

Gait Kinematics And Kinetics Are Affected More By Peripheral Arterial Disease Than By Age, Sara A. Myers, Bryon Applequist, Jessie M. Huisinga, Iraklis Pipinos, Jason M. Johanning

Journal Articles

—Peripheral arterial disease (PAD) produces abnormal gait and disproportionately affects older individuals. The current study investigated PAD gait biomechanics in younger (<65 yr) and older (>/=65 yr) subjects. The study included 61 patients with PAD (31 younger, age: 57.4 +/– 5.3 yr, and 30 older, age: 71.9 +/– 5.2 yr) and 52 nondisabled age-matched control subjects. Patients with PAD were tested during pain-free walking and compared with control subjects. Joint kinematics and kinetics (torques) were compared using a 2 x 2 analysis of variance (groups: patients with PAD vs control subjects, age: younger vs older). Patients with PAD had significantly increased ankle and …

Quantifying Muscle Fatigue Of The Low Back During Repetitive Load Lifting Using Lyapunov Analysis, Elias Spyropoulos, Anastasia Kyvelidou, Nicholas Stergiou, George Athanassiou

Journal Articles

Background: Occupational low back disorders are often associated with exposure to work-related physical risk factors such as muscle fatigue in the low back.
Objective: The objective of this study was to investigate the possible relationship between the divergence of the kinematic trajectories of the low back system and the different stages of fatigue during the execution of a repetitive lifting task.
Methods: The patterns of the low back system were recorded using markers on specific vertebras during the repetitive load lifting from the floor to a 0.75 m height table. The maximum Lyapunov exponent, λmax of the recorded patterns was …

Effects Of Whole Body Vibration Training On Body Composition, Skeletal Muscle Strength, And Cardiovascular Health, Song-Young Park, Won-Mok Son, Oh-Sung Kwon

Health and Kinesiology Faculty Publications

Whole body vibration training (WBVT) has been used as a supplement to conventional exercise training such as resistance exercise training to improve skeletal muscle strength, specifically, in rehabilitation field. Recently, this exercise modality has been utilized by cardiovascular studies to examine whether WBVT can be a useful exercise modality to improve cardiovascular health. These studies reported that WBVT has not only beneficial effects on muscular strength but also cardiovascular health in elderly and disease population. However, its mechanism underlying the beneficial effects of WBVT in cardiovascular health has not been well documented. Therefore, this review highlighted the impacts of WBVT …

The Effects Of Aerobic Exercise Training On Blood Lipid Profiles, Fibrinolytic Activities, And Nitric Oxide Levels In High-Fat-Diet Induced Rats, Won-Mok Son, Do-Yeon Kim, Ki-Dong Sung, Yi Sub Kwak, Yeong Ho Baek, Song-Young Park

Health and Kinesiology Faculty Publications

Although exercise training has been utilized to improve vascular function in animals and humans, the impact of moderate intensity exercise training on fibrinolytic activities and nitric oxide (NO) bioavailability has not been well documented. Therefore, the purpose of the current study was to examine the impact of moderate intensity aerobic exercise training on fat mass, blood lipid profiles, fibrinolytic activity, and NO levels in high-fat-diet induced rats. The body weight, fat mass, blood lipid profiles, fibrinolytic activity, and nitrite/nitrate were measured pre- and postexercise (10 weeks) training. The body weight and fat mass reduced significantly in the exercise (EX) group …

Increased Minimum Toe Clearance Variability In Patients With Peripheral Arterial Disease, Troy Rand, Shane R. Wurdeman, Jason M. Johanning, Iraklis Pipinos, Sara A. Myers

Journal Articles

Individuals with peripheral arterial disease (PAD) report difficulty walking and experience 73% more falls than their healthy counterparts, but no studies have investigated functional mechanisms contributing to increased falls. Minimum toe clearance (MTC) is the minimum vertical distance between the toe of the swinging leg and the walking surface when the leg is swinging, and decreased values are associated with an increased risk for falls. This study is the first such analysis in patients with PAD. Eighteen individuals with PAD and eighteen healthy controls walked on a treadmill before and after the onset of claudication pain. Mean MTC and the …

The Clinical Evaluation Between Overtraining Syndrome And Exercise-Related Immunity, Song-Young Park, Yi Sub Kwak, Seung-Jun Choi

Health and Kinesiology Faculty Publications

The present study was performed to analyze and review the physical and immune responses to overtraining syndrome in humans. Overreaching refers to the initial phage of overtraining syndrome and has been known as a physical fatigue which is mainly from metabolic imbalance. It has been known that overtraining also results in a loss of adaptability which may lead to an attenuation of exercise performance, sleeping disorder, central fatigue, neurohormonal changes, difficulty recovery to physical stress, and immunological changes. Additionally, overtraining syndrome is characterized by persistent fatigue, poor performance in sport due to the prolonged and strenuous physical training. Also, previous …

Step Activity And Stride-To-Stride Fluctuations Are Negatively Correlated In Individuals With Transtibial Amputation, Jenny A. Kent, Nicholas Stergiou, Shane Wurdeman

Journal Articles

Background

Variability occurs naturally from stride to stride in healthy gait. It has been shown that individuals with lower limb loss have significantly increased stride-to-stride fluctuations during walking. This is considered indicative of movement disorganization and is associated with less healthy movement. Given that lower limb prosthesis users perform on average less physical activity than able bodied individuals, the purpose of this study was to determine whether increased fluctuations also correspond to a reduced level of activity in daily life.

Methods

Twenty-two transtibial amputees wore an activity monitor (Actigraph, Pensacola, FL, USA) for 3 weeks. Lower limb kinematics during treadmill …

Optic Flow Improves Adaptability Of Spatiotemporal Characteristics During Split-Belt Locomotor Adaptation With Tactile Stimulation, Diderik Jan Anthony Eikema, Jung Chien, Nicholas Stergiou, Sara Myers, Melissa Scott-Pandorf, Jacob J. Bloomberg, Mukul Mukherjee

Journal Articles

Human locomotor adaptation requires feedback and feed-forward control processes to maintain an appropriate walking pattern. Adaptation may require the use of visual and proprioceptive input to decode altered movement dynamics and generate an appropriate response. After a person transfers from an extreme sensory environment and back, as astronauts do when they return from spaceflight, the prolonged period required for re-adaptation can pose a significant burden. In our previous paper, we showed that plantar tactile vibration during a split-belt adaptation task did not interfere with the treadmill adaptation however, larger overground transfer effects with a slower decay resulted. Such effects, in …

Quadriceps Exercise Intolerance In Patients With Chronic Obstructive Pulmonary Disease: The Potential Role Of Altered Skeletal Muscle Mitochondrial Respiration, J. R. Gifford, Joel D. Trinity, Gwenael Layec, Ryan S. Garten, Song-Young Park, Matthew J. Rossman, Steen Larsen, Flemming Dela, Russell S. Richardson

Health and Kinesiology Faculty Publications

This study sought to determine if qualitative alterations in skeletal muscle mitochondrial respiration, associated with decreased mitochondrial efficiency, contribute to exercise intolerance in patients with chronic obstructive pulmonary disease (COPD). Using permeabilized muscle fibers from the vastus lateralis of 13 patients with COPD and 12 healthy controls, complex I (CI) and complex II (CII)-driven State 3 mitochondrial respiration were measured separately (State 3:CI and State 3:CII) and in combination (State 3:CI+CII). State 2 respiration was also measured. Exercise tolerance was assessed by knee extensor exercise (KE) time to fatigue. Per milligram of muscle, State 3:CI+CII and State 3:CI were reduced …

University Of Nebraska At Omaha Biomechanics Annual Report, Fall 2015, Biomechanics Research Building

Biomechanics Annual Report

This annual report includes:

Letter from the Director; B.S. in Biomechanics; QLI Partnership

Center for Research in Human Movement Variability: Formation of the Center; Breathing and Walking Coupling Variability in COPD; Gait Variability in Patients with Peripheral Arterial Disease; Development of Postural Control Variability in Autism; The Effects of Virtual Reality on Gait Variability After Stroke; Pilot Grants; COBRE Research Day; New Hires in the Center

Updates: Why Choose the BRB? Where Are They Now? From the Bench to the Market: New Partnership Paves the way to Pre-Symptomatic Disease Detection; Fun Facts; New Quipment

Other Projects: Space Navigation; Neuroscience; Prosthetics; …

Locomotor Sensory Organization Test: How Sensory Conflict Affects The Temporal Structure Of Sway Variability During Gait, Jung Hung Chien, Mukul Mukherjee, Ka-Chun Siu, Nikolaos Stergiou

Journal Articles

When maintaining postural stability temporally under increased sensory conflict, a more rigid response is used where the available degrees of freedom are essentially frozen. The current study investigated if such a strategy is also utilized during more dynamic situations of postural control as is the case with walking. This study attempted to answer this question by using the Locomotor Sensory Organization Test (LSOT). This apparatus incorporates SOT inspired perturbations of the visual and the somatosensory system. Ten healthy young adults performed the six conditions of the traditional SOT and the corresponding six conditions on the LSOT. The temporal structure of …

Patterns Of Dominance Relationships Among The Females Of A Captive Female-Only Group Of Lion-Tailed Macaques (Macaca Silenus) During The Course Of The Introduction Of A New Adult Male, Pia Zaunmair, Madhur Mangalam, Werner Kaumanns, Mewa Singh, Leopold Slotta-Bachmayr

Journal Articles

Lion-tailed macaques are generally considered to have more despotic than egalitarian dominance relationships; however, research lacks any conclusive evidence. In the present study, we examined dominance relationships among the females (of which the genealogical relationships were known) of a captive female-only group of lion-tailed macaques (Macaca silenus) during the course of introduction of a new adult male to the group at the Wels Zoo, Wels, Austria. We determined the structure of dominance hierarchy and the corresponding changes in dominance relationships, possibly mediated by an increase in sexual competition among the females. When the females were housed together without any adult …

How To Sync To The Beat Of A Persistent Fractal Metronome Without Falling Off The Treadmill?, Melvyn Roerdink, Andreas Daffertshofer, Vivien Marmelat, Peter J. Beek

Journal Articles

In rehabilitation, rhythmic acoustic cues are often used to improve gait. However, stride-time fluctuations become anti-persistent with such pacing, thereby deviating from the characteristic persistent long-range correlations in stride times of self-paced walking healthy adults. Recent studies therefore experimented with metronomes with persistence in interbeat intervals and successfully evoked persistent stride-time fluctuations. The objective of this study was to examine how participants couple their gait to a persistent metronome, evoking persistently longer or shorter stride times over multiple consecutive strides, without wandering off the treadmill. Twelve healthy participants walked on a treadmill in self-paced, isochronously paced and non-isochronously paced conditions, …

Plantar Tactile Perturbations Enhance Transfer Of Split-Belt Locomotor Adaptation, Mukul Mukherjee, Diderik Jan Anthony Eikema, Jung Hung Chien, Sara A. Myers, Melissa Scott-Pandorf, Jacob J. Bloomberg, Nikolaos Stergiou

Journal Articles

Patterns of human locomotion are highly adaptive and flexible and depend on the environmental context. Locomotor adaptation requires the use of multisensory information to perceive altered environmental dynamics and generate an appropriate movement pattern. In this study, we investigated the use of multisensory information during locomotor learning. Proprioceptive perturbations were induced by vibrating tactors, placed bilaterally over the plantar surfaces. Under these altered sensory conditions, participants were asked to perform a split-belt locomotor task representative of motor learning. Twenty healthy young participants were separated into two groups: no-tactors (NT) and tactors (TC). All participants performed an overground walking trial, followed …

Human Movement Variability And Aging, Nicholas Stergiou, Jenny A. Kent, Denise Mcgrath

Journal Articles

An optimal level of variability enables us to interact adaptively and safely to a continuously changing environment, where often our movements must be adjusted in a matter of milliseconds. A large body of research exists that demonstrates natural variability in healthy gait (along with variability in other, healthy biological signals such as heart rate) and a loss of this variability in aging and injury, as well as in a variety of neurodegenerative and physiological disorders. We submit that this field of research is now in pressing need of an innovative “next step” that goes beyond the many descriptive studies that …

Subjective Reports And Postural Performance Among Older Adult Passengers On A Sea Voyage, Justin Munafo, Michael G. Wade, Nicholas Stergiou, Thomas A. Stoffregen

Journal Articles

We sought to evaluate changes in subjective experience and postural performance among older adult passengers during the first 2 days of a sea voyage. On a vacation cruise, volunteer passengers gave verbal ratings of subjective bodily stability and awareness of ship motion followed by performance on the tandem Romberg test while facing fore-aft and athwartship. Data were collected when the ship was at the dock and on each of the first 2 full days at sea. Ship motion reduced subjective bodily stability and performance on the Romberg test and increased awareness of ship motion. On the first day at sea, …

Temporal Structure Of Support Surface Translations Drive The Temporal Structure Of Postural Control During Standing, Troy J. Rand, Sara A. Myers, Anastasia Kyvelidou, Mukul Mukherjee

Journal Articles

A healthy biological system is characterized by a temporal structure that exhibits fractal properties and is highly complex. Unhealthy systems demonstrate lowered complexity and either greater or less predictability in the temporal structure of a time series. The purpose of this research was to determine if support surface translations with different temporal structures would affect the temporal structure of the center of pressure (COP) signal. Eight healthy young participants stood on a force platform that was translated in the anteroposterior direction for input conditions of varying complexity: white noise, pink noise, brown noise, and sine wave. Detrended fluctuation analysis was …

Low Intensity Resistance Exercise Training With Blood Flow Restriction: Insight Into Cardiovascular Function, And Skeletal Muscle Hypertrophy In Humans, Song-Young Park, Yi Sub Kwak, Andrew Harveson, Joshua C. Weavil, Kook E. Seo

Health and Kinesiology Faculty Publications

Attenuated functional exercise capacity in elderly and diseased populations is a common problem, and stems primarily from physical inactivity. Decreased function and exercise capacity can be restored by maintaining muscular strength and mass, which are key factors in an independent and healthy life. Resistance exercise has been used to prevent muscle loss and improve muscular strength and mass. However, the intensities necessary for traditional resistance training to increase muscular strength and mass may be contraindicated for some at risk populations, such as diseased populations and the elderly. Therefore, an alternative exercise modality is required. Recently, blood flow restriction (BFR) with …

Mechanisms To Increase Propulsive Force For Individuals Poststroke, Haoyuan Hsiao, Brian A. Knarr, Jill S. Higginson, Stuart A. Binder-Macleod

Journal Articles

Background: Propulsive force generation is critical to walking speed. Trialing limb angle and ankle moment are major contributors to increases in propulsive force during gait. For able-bodied individuals, trailing limb angle contributes twice as much as ankle moment to increases in propulsive force during speed modulation. The aim of this study was to quantify the relative contribution of ankle moment and trailing limb angle to increases in propulsive force for individuals poststroke.

Methods: A biomechanical-based model previously developed for able-bodied individuals was evaluated and enhanced for individuals poststroke. Gait analysis was performed as subjects (N = 24) with …

Biomechanical Analyses Of Stair-Climbing While Dual-Tasking, Srikant Vallabhajosula, Chi Wei Tan, Mukul Mukherjee, Austin Davidson, Nicholas Stergiou

Journal Articles

Stair-climbing while doing a concurrent task like talking or holding an object is a common activity of daily living which poses high risk for falls. While biomechanical analyses of overground walking during dual-tasking have been studied extensively, little is known on the biomechanics of stair-climbing while dual-tasking. We sought to determine the impact of performing a concurrent cognitive or motor task during stair-climbing. We hypothesized that a concurrent cognitive task will have a greater impact on stair climbing performance compared to a concurrent motor task and that this impact will be greater on a higher-level step. Ten healthy young adults …

Sitting Postural Control Affects The Development Of Focused Attention In Children With Cerebral Palsy, Swati Surkar, Christina Edelbrock, Nicholas Stergiou, Sarah Berger, Regina T. Harbourne

Journal Articles

Purpose:

To investigate whether focused attention (FA) changes over time as sitting postural control improves and whether an impairment in sitting postural control affects the development of FA in children with cerebral palsy (CP).

Methods:

Nineteen children with CP, mean ages 21.47 months, were assessed for FA and sitting scores pre- and postintervention.

Results:

Longest, total, and global FA increased and frequency of FA decreased in children who achieved independent sitting. However, children who achieved mobility postintervention exhibited a decrease in longest FA and an increase in frequency of FA.

Conclusion:

Sitting postural control and the development of FA appear …

Why Not Be An Early-Bird Researcher?, Ravindra P. Nettimi, Madhur Mangalam, Mewa Singh

Journal Articles

No abstract provided.

Division Of Labor In Hand Usage Is Associated With Higher Hand Performance In Free-Ranging Bonnet Macaques, Macaca Radiata, Madhur Mangalam, Nisarg Desai, Mewa Singh

Journal Articles

A practical approach to understanding lateral asymmetries in body, brain, and cognition would be to examine the performance advantages/disadvantages associated with the corresponding functions and behavior. In the present study, we examined whether the division of labor in hand usage, marked by the preferential usage of the two hands across manual operations requiring maneuvering in three-dimensional space (e.g., reaching for food, grooming, and hitting an opponent) and those requiring physical strength (e.g., climbing), is associated with higher hand performance in free-ranging bonnet macaques, Macaca radiata. We determined the extent to which the macaques exhibit laterality in hand usage in …

Lower Extremity Kinematics During A Drop Jump In Individuals With Patellar Tendinopathy, Adam B. Rosen, Jupil Ko, Kathy J. Simpson, Seock-Ho Kim, Cathleen N. Brown

Journal Articles

Background: Patellar tendinopathy (PT) is a common degenerative condition in physically active populations. Knowledge regarding the biomechanics of landing in populations with symptomatic PT is limited, but altered mechanics may play a role in the development or perpetuation of PT.

Purpose: To identify whether study participants with PT exhibited different landing kinematics compared with healthy controls.

Study Design: Controlled laboratory study.

Methods: Sixty recreationally active participants took part in this study; 30 had current signs and symptoms of PT, including self-reported pain within the patellar tendon during loading activities for at least 3 months and ≤80 on the Victorian Institute …