Biomechanics Commons^™

Simulated Hearing Loss In Healthy Young And Older Adults Results In Poor Reaction Time In Older Adults., Victoria Kowalewski, Nicoleta Bugnariu, Rita M. Patterson, Jessica Hartos

Pacific Journal of Health

Emerging evidence links hearing loss to increased fall risk in older adults, yet mechanisms remain unclear. This study examined the impact of simulated hearing loss on reactive balance control in healthy young and older adults. Participants performed dual-task scenario involving auditory sentence repetition and unexpected surface translations. Hearing loss was simulated using Adobe Audition, applying frequency-specific attenuation based on moderate sensorineural hearing loss levels from the literature.

Speech-in-noise performance significantly declined under simulated hearing loss for both age groups (p < .001), confirming effective simulation, but not significant differences were found between age groups. Maximum COP-COM displacement (the scalar distance between Center of Pressure and Center of Mass) increased with perturbation intensity (Level 1 vs. Level 2: p < .001), but no significant differences were found between hearing conditions or age groups (p > .05), suggesting compensatory step execution was preserved.

Reaction time analysis revealed a significant interaction between hearing condition and perturbation level …

Quantifying Physical Function: Moving Towards A New Definition And Better Assessment, Anthony Campitelli

Graduate Theses and Dissertations

Though poor physical function (PF) and disability are two of the most impactful problems facing older adults today, the field of kinesiology has not yet devised a method of measuring PF, thus limiting investigations with the potential to lead to improved PF interventions and assessments. This dissertation aimed to develop a single, continuous measure of PF using a latent variable modeling approach, and then use the generated scores to evaluate the role of lower body muscular power in PF assessment and to construct an improved PF assessment battery for predicting overall PF. Each aim of this dissertation was addressed through …

Quantifying Balance: Computational And Learning Frameworks For The Characterization Of Balance In Bipedal Systems, Kubra Akbas

Dissertations

In clinical practice and general healthcare settings, the lack of reliable and objective balance and stability assessment metrics hinders the tracking of patient performance progression during rehabilitation; the assessment of bipedal balance plays a crucial role in understanding stability and falls in humans and other bipeds, while providing clinicians important information regarding rehabilitation outcomes. Bipedal balance has often been examined through kinematic or kinetic quantities, such as the Zero Moment Point and Center of Pressure; however, analyzing balance specifically through the body's Center of Mass (COM) state offers a holistic and easily comprehensible view of balance and stability.

Building upon …

Obstacle Crossing In Healthy Young And Older Individuals, Hope M. Hanson, Ashlyn M. Jendro, Abigail C. Schmitt

Health, Human Performance and Recreation Undergraduate Honors Theses

Introduction: In the United States, the average population age is rising and will continue to increase in the coming years.With an older population comes increased risk of injury associated with falls. Falls are considered a leading cause of injury and death in older individuals, and many falls are caused by body imbalance or obstacle collision due to a clearly visible stationary object (e.g., rug, chair, branch). Older adults tend to cross obstacles with increased toe clearance in order to prevent tripping, but much of what is known about obstacle crossing in older adults is limited to artificial obstacles that are …

Decoding Human Movement Through Experiments And Simulation, Vishnu Deep Chandran

Dissertations

The ability to walk or move independently plays a decisive role in one's quality of life. This human ability requires complex coordination with several systems, such as the nervous, muscular, skeletal, and sensory organs, to execute movement tasks. Hence, any disorder of these systems from injury, disease, or aging severely affects the ability to walk or move independently. Disabilities that impair movement severely affect the quality of life. Therefore, studying the changes affecting human movement is necessary to improve the lives of individuals with impaired movement. Since human movement is complex and many systems interact in non-intuitive ways, the overarching …

Self-Selected Maximum But Not Jogging Speed Decreases With Age In Male And Female Runners, Heather Hamilton, Rumit Singh Kakar

College of Health Sciences Posters

Introduction: Running velocity decreases with age, likely resulting from physiological and musculoskeletal changes associated with aging. Females experience a more rapid decline in physical performance during middle age than males, therefore it is important to consider separate-sex analyses when studying running biomechanics and running-related injury. The purpose of this study was to determine the relationship between age and different running speeds separately for female and male runners.

Methods: Male (n=33) and female (n=46) runners (ages 18–65 years) ran at their self-selected JOG (long distance) and MAX (maximal running) pace on a treadmill. Running velocity was recorded. Simple linear regression was …

Gait Complexity Is Acutely Restored In Older Adults When Walking To A Fractal-Like Visual Stimulus, Joao R. Vaz, Brian Knarr, Nicholas Stergiou

Journal Articles

Typically, gait rehabilitation uses an invariant stimulus paradigm to improve gait related deficiencies. However, this approach may not be optimal as it does not incorporate gait complexity, or in more precise words, the variable fractal-like nature found in the gait fluctuations commonly observed in healthy populations. Aging which also affects gait complexity, resulting in a loss of adaptability to the surrounding environment, could benefit from gait rehabilitation that incorporates a variable fractal-like stimulus paradigm. Therefore, the present study aimed to investigate the effect of a variable fractal-like visual stimulus on the stride-to-stride fluctuations of older adults during overground walking. Additionally, …

Aging, Gait Variability, And Adaptability, Collin Douglas Bowersock

Health Services Research Dissertations

The purpose of this work was to study the relationships between age, measures of gait variability, and locomotor adaptability. Measures of gait variability are used to identify maladapted locomotor behavior, motor disease, and risk of falls. The first aim was to determine the relationships between age and measures of gait variability. Thirty-four participants (23-71 years old) walked on a treadmill for 6 minutes at their preferred speed. Variability of stride times and lengths was computed via linear measures (standard deviation and coefficient of variation) and nonlinear measures (sample entropy and detrended fluctuation analysis). Movement trajectory variability of the dominant knee …

Assessing The Temporal Organization Of Walking Variability: A Systematic Review And Consensus Guidelines On Detrended Fluctuation Analysis, Deepak K. Ravi, Vivien Marmelat, William R. Taylor, Karl M. Newell, Nicholas Stergiou, Navrag B. Singh

Journal Articles

Human physiological signals are inherently rhythmic and have a hallmark feature in that even distant intrasignal measurements are related to each other. This relationship is termed long-range correlation and has been recognized as an indicator of the optimal state of the observed physiological systems, among which the locomotor system. Loss of long-range correlations has been found as a result of aging as well as disease, which can be evaluated with detrended fluctuation analysis (DFA). Recently, DFA and the scaling exponent α have been employed for understanding the degeneration of temporal regulation of human walking biorhythms in, for example, Parkinson disease …

Biomechanics In The 4haie Study: Air Pollution And Musculoskeletal Health - An Update, Daniel Jandacka, Jaroslav Uchityil, David Zahradník, Roman Farana, Dominik Villimek, Jiri Skypala, Jan Urbaczka, Jan Plesek, Adam Motyka, Denisa Blaschova, Gabriela Beinhauerova, Marketa Rygelová, Pavel Brtva, Zuzana Golembiovska, Klara Balazova, Jan Malus, Veronika Horka, Julia F. Silvernail, Gareth Irwin, Miika T. Nieminen, Victor Casula, Vlado Juras, Milos Golian, Steriani Elavsky, Lenka Knapova, Radim Sram, Joseph Hamill

Kinesiology and Nutrition Sciences Faculty Research

The overall purpose of the 4HAIE study was to assess the influence of the interaction between air pollution and biomechanical, physiological and psychosocial factors on the incidence of injuries, health and well-being. A total of 1,500 active runners and inactive controls aged 18-65 will be recruited. Herein, we describe the biomechanical study design with data examples to investigate musculoskeletal and neuro-mechanics health in different air quality regions.

Serum Myostatin And Igf-1 As Biomarkers Of Sarcopenia: A Proof-Of-Concept Design, Ashley Binns

Graduate Theses and Dissertations

The population comprising older adults is growing exponentially, as are healthcare related costs. Nearly $20 billion is annually expensed by older adults for health-related issues affiliated with age-related decline in skeletal muscle mass. Yet, diagnostic criteria are not readily utilized in clinical practice. PURPOSE: Therefore, the purpose of this study was to provide evidence for use of blood biomarkers (myostatin, IGF-1) to predict appendicular skeletal muscle mass (ASM) among middle-aged and older adults. METHODS: A cross-sectional study was conducted among 106 individuals (n = 68 females; n = 38 males) aged ≥ 40 years of age (60.1 ± 11.1 y) …

Posture And Gaze Tracking Of A Vertically Moving Target Reveals Age-Related Constraints In Visuo-Motor Coupling, Haralampos Sotirakis, Anastasia Kyvelidou, Nicholas Stergiou, Vassilia Hatzitaki

Journal Articles

Previously we have demonstrated that the effect of aging on posture and gaze active tracking of a visual target moving in the horizontal direction is dependent on target’s complexity. In this study, we asked whether a similar phenomenon is present when tracking a visual target moving with varying complexity in the vertical direction. Ten young (22.98 ± 2.9 years) and 10 older adults (72.45 ± 4.72 years) tracked for 120 s, a visual target moving vertically by shifting their bodyweight in the anterior-posterior direction. Three target motions were tested: a simple periodic (sine wave), a more complex (Lorenz attractor) and …

Effects Of Aging On The Relationship Between Cognitive Demand And Step Variability During Dual-Task Walking, Leslie M. Decker, Fabien Cignetti, Nathaniel Hunt, Jane F. Potter, Nicholas Stergiou, Stephanie A. Studenski

Journal Articles

A U-shaped relationship between cognitive demand and gait control may exist in dual-task situations, reflecting opposing effects of external focus of attention and attentional resource competition. The purpose of the study was twofold: to examine whether gait control, as evaluated from step-to-step variability, is related to cognitive task difficulty in a U-shaped manner and to determine whether age modifies this relationship. Young and older adults walked on a treadmill without attentional requirement and while performing a dichotic listening task under three attention conditions: non-forced (NF), forced-right (FR), and forced-left (FL). The conditions increased in their attentional demand and requirement for …

Aging Affects Postural Tracking Of Complex Visual Motion Cues, Haralampos Sotirakis, Anastasia Kyvelidou, L. Mademli, Nicholas Stergiou, Vassilia Hatzitaki

Journal Articles

Postural tracking of visual motion cues improves perception–action coupling in aging, yet the nature of the visual cues to be tracked is critical for the efficacy of such a paradigm. We investigated how well healthy older (72.45 ± 4.72 years) and young (22.98 ± 2.9 years) adults can follow with their gaze and posture horizontally moving visual target cues of different degree of complexity. Participants tracked continuously for 120 s the motion of a visual target (dot) that oscillated in three different patterns: a simple periodic (simulated by a sine), a more complex (simulated by the Lorenz attractor that is …

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 …

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

Attractor Divergence As A Metric For Assessing Walking Balance, Max J. Kurz, Katerina Markopoulou, Nikolaos Stergiou

Journal Articles

: Individuals with Parkinson's disease and the aged have a high prevalence of falls. Since an increase in the number of falls is associated with physical and psychological harm, it is prudent that biomechanical metrics be established that will accurately assess an individual's walking balance. In this investigation, we initially used a simple bipedal walking computer model to theoretically establish the relationship between attractor divergence and walking balance. The Lyapunov exponent was used to quantify the amount of divergence present in the walking attractor. Simulations from our model indicated that attractors that have a greater amount of divergence are more …

Complexity And Human Gait, Leslie M. Decker, Fabien Cignetti, Nikolaos Stergiou

Journal Articles

Recently, the complexity of the human gait has become a topic of major interest within the field of human movement sciences. Indeed, while the complex fluctuations of the gait patterns were, for a long time, considered as resulting from random processes, the development of new techniques of analysis, so-called nonlinear techniques, has open new vistas for the understanding of such fluctuations. In particular, by connecting the notion of complexity to the one of chaos, new insights about gait adaptability, unhealthy states in gait and neural control of locomotion were provided. Through methods of evaluation of the complexity, experimental results obtained …

Nonlinear Analysis Of Ambulatory Activity Patterns In Community-Dwelling Older Adults, James T. Cavanaugh, Naomi Kochi, Nikolaos Stergiou

Journal Articles

Background The natural ambulatory activity patterns of older adults are not well understood. User-worn monitors illuminate patterns of ambulatory activity and generate data suitable for analysis using measures derived from nonlinear dynamics.

MethodsAmbulatory activity data were collected continuously from 157 community-dwelling older adults for 2 weeks. Participants were separated post hoc into groups based on the mean number of steps per day: highly active (steps ≥ 10,000), moderately active (5,000 ≤ steps < 10,000 steps), and inactive (steps

Results All groups displayed patterns of fluctuating step count values containing complex temporal structure. DFA, ER, and ApEn parameter values increased monotonically and significantly with increasing activity …

Aging And Partial Body Weight Support Affects Gait Variability, Anastasia Kyvelidou, Max J. Kurz, Julie L. Ehlers, Nikolaos Stergiou

Journal Articles

Background: Aging leads to increases in gait variability which may explain the large incidence of falls in the elderly. Body weight support training may be utilized to improve gait in the elderly and minimize falls. However, before initiating rehabilitation protocols, baseline studies are needed to identify the effect of body weight support on elderly gait variability. Our purpose was to determine the kinematic variability of the lower extremities in young and elderly healthy females at changing levels of body weight support during walking.

Methods: Ten young and ten elderly females walked on a treadmill for two minutes with a body …

Original Investigation Correlated Joint Fluctuations Can Influence The Selection Of Steady State Gait Patterns In The Elderly, Max J. Kurz, Nikolaos Stergiou

Journal Articles

This investigation utilized a Markov model to investigate the relationship of correlated lower extremity joint fluctuations and the selection of a steady state gait pattern in the young and elderly. Our model simulated the neuromuscular system by predicting the behavior of the joints for the next gait cycle based on the behavior exhibited in the preceding gait cycles. Such dependencies in the joint fluctuations have been noted previously in the literature. We speculated that compared to the young model, the characteristics of the correlated fluctuations in the elderly model would result in the selection of a different steady state gait …