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Full-Text Articles in Life Sciences

Gait Characteristics And Falls In Parkinson's Disease: A Systematic Review And Meta-Analysis [Accepted Manuscript], Mark W. Creaby, Michael H. Cole Dec 2018

Gait Characteristics And Falls In Parkinson's Disease: A Systematic Review And Meta-Analysis [Accepted Manuscript], Mark W. Creaby, Michael H. Cole

Faculty of Health Sciences Publications

Introduction: Given the high rate of falls during walking in people with idiopathic Parkinson's disease (PD), identifying at risk individuals and developing targeted interventions to reduce falls incidence is paramount. Numerous studies have investigated gait-related risk factors for falls in PD, however findings are inconsistent across studies, and thus a synthesis of the current evidence is needed to guide clinical practice and the development of interventions to reduce falls risk. The objective of this study was to systematically review the literature regarding the association between walking biomechanics and falls in people with PD, and where possible, perform meta-analyses. Methods ...


Linking Gait Dynamics To Mechanical Cost Of Legged Locomotion, David V. Lee, Sarah L. Harris Oct 2018

Linking Gait Dynamics To Mechanical Cost Of Legged Locomotion, David V. Lee, Sarah L. Harris

Life Sciences Faculty Publications

For millenia, legged locomotion has been of central importance to humans for hunting, agriculture, transportation, sport, and warfare. Today, the same principal considerations of locomotor performance and economy apply to legged systems designed to serve, assist, or be worn by humans in urban and natural environments. Energy comes at a premium not only for animals, wherein suitably fast and economical gaits are selected through organic evolution, but also for legged robots that must carry sufficient energy in their batteries. Although a robot's energy is spent at many levels, from control systems to actuators, we suggest that the mechanical cost ...


On The Choice Of Multiscale Entropy Algorithm For Quantification Of Complexity In Gait Data, Peter C. Raffalt, William Denton, Jennifer M. Yentes Oct 2018

On The Choice Of Multiscale Entropy Algorithm For Quantification Of Complexity In Gait Data, Peter C. Raffalt, William Denton, Jennifer M. Yentes

Journal Articles

The present study aimed at identifying a suitable multiscale entropy (MSE) algorithm for assessment of complexity in a stride-to-stride time interval time series. Five different algorithms were included (the original MSE, refine composite multiscale entropy (RCMSE), multiscale fuzzy entropy, generalized multiscale entropy and intrinsic mode entropy) and applied to twenty iterations of white noise, pink noise, or a sine wave with added white noise. Based on their ability to differentiate the level of complexity in the three different generated signal types, and their sensitivity and parameter consistency, MSE and RCMSE were deemed most appropriate. These two algorithms were applied to ...


Exoskeleton Assistance Symmetry Matters: Unilateral Assistance Reduces Metabolic Cost, But Relatively Less Than Bilateral Assistance, Philippe Malcolm, Samuel Galle, Pieter Van Den Berghe, Dirk De Clercq Aug 2018

Exoskeleton Assistance Symmetry Matters: Unilateral Assistance Reduces Metabolic Cost, But Relatively Less Than Bilateral Assistance, Philippe Malcolm, Samuel Galle, Pieter Van Den Berghe, Dirk De Clercq

Journal Articles

Background: Many gait impairments are characterized by asymmetry and result in reduced mobility. Exoskeletons could be useful for restoring gait symmetry by assisting only one leg. However, we still have limited understanding of the effects of unilateral exoskeleton assistance. Our aim was to compare the effects of unilateral and bilateral assistance using a within-subject study design.

Methods: Eleven participants walked in different exoskeleton conditions. In the Unilateral conditions, only one leg was assisted. In Bilateral Matched Total Work, half of the assistance from the Unilateral conditions was applied to both legs such that the bilateral sum was equal to that ...


Bi-Articular Knee-Ankle-Foot Exoskeleton Produces Higher Metabolic Cost Reduction Than Weight-Matched Mono-Articular Exoskeleton, Philippe Malcolm, Samuel Galle, Dirk De Clercq Mar 2018

Bi-Articular Knee-Ankle-Foot Exoskeleton Produces Higher Metabolic Cost Reduction Than Weight-Matched Mono-Articular Exoskeleton, Philippe Malcolm, Samuel Galle, Dirk De Clercq

Journal Articles

The bi-articular m. gastrocnemius and the mono-articular m. soleus have different and complementary functions during walking. Several groups are starting to use these biological functions as inspiration to design prostheses with bi-articular actuation components to replace the function of the m. gastrocnemius. Simulation studies indicate that a bi-articular configuration and spring that mimic the m. gastrocnemius could be beneficial for orthoses or exoskeletons. Our aim was to test the effect of a bi-articular and spring configuration that mimics the m. gastrocnemius and compare this to a no- spring and mono-articular configuration. We tested nine participants during walking with knee-ankle-foot exoskeletons ...


Stepping It Up: Walking Behaviors In Children Transitioning From 5th To 7th Grade, Sharon E. Taverno Ross, Morgan N. Clennin, Marsha Dowda, Natalie Colabianchi, Russell R. Pate Feb 2018

Stepping It Up: Walking Behaviors In Children Transitioning From 5th To 7th Grade, Sharon E. Taverno Ross, Morgan N. Clennin, Marsha Dowda, Natalie Colabianchi, Russell R. Pate

Faculty Publications

The purpose of this study was to (1) describe children’s walking behaviors in 5th to 7th grade and change over time and (2) examine associations between walking behaviors and Walk Score®. Participants consisted of n = 586 students from the Transitions and Activity Changes in Kids (TRACK) Study. Children reported any walking behavior (e.g., exercise and transportation) over the past five days. Walk Score was calculated based on children’s home address. Descriptive statistics summarized walking behaviors by gender and time, and repeated measure mixed models examined the relationship between walking behaviors and Walk Score. Approximately 46.8% and ...


Introducing Statistical Persistence Decay – A Quantification Of Stride-To-Stride Time Interval Dependency In Human Gait, P. C. Raffalt, J. M. Yentes Jan 2018

Introducing Statistical Persistence Decay – A Quantification Of Stride-To-Stride Time Interval Dependency In Human Gait, P. C. Raffalt, J. M. Yentes

Journal Articles

Stride-to-stride time intervals during human walking are characterised by predictability and statistical persistence quantified by sample entropy (SaEn) and detrended fluctuation analysis (DFA) which indicates a time dependency in the gait pattern. However, neither analyses quantify time dependency in a physical or physiological interpretable time scale. Recently, entropic half-life (ENT½) has been introduced as a measure of the time dependency on an interpretable time scale. A novel measure of time dependency, based on DFA, statistical persistence decay (SPD), was introduced. The present study applied SaEn, DFA, ENT½, and SPD in known theoretical signals (periodic, chaotic, and random) and stride-to-stride time ...


Development And Reliability Off A Streetscape Observation Instrument For International Use: Maps-Global, Kelli Cain, Carrie M. Geremia, Terry Conway, Lawrence Frank, James Chapman, Eric H. Fox, Anna Timperio, Jenny Veitch, Delfien Van Dyck, Hannah Verhoeven, Rodrigo Reis, Alexande Augusto, Ester Cerin, Robin Mellecker, Ana Queralt, Javier Molina-Garcia, Jim Sallis Jan 2018

Development And Reliability Off A Streetscape Observation Instrument For International Use: Maps-Global, Kelli Cain, Carrie M. Geremia, Terry Conway, Lawrence Frank, James Chapman, Eric H. Fox, Anna Timperio, Jenny Veitch, Delfien Van Dyck, Hannah Verhoeven, Rodrigo Reis, Alexande Augusto, Ester Cerin, Robin Mellecker, Ana Queralt, Javier Molina-Garcia, Jim Sallis

Faculty of Health Sciences Publications

Background: Relationships between several built environment factors and physical activity and walking behavior are well established, but internationally-comparable built environment measures are lacking. The Microscale Audit of Pedestrian Streetscapes (MAPS)-Global is an observational measure of detailed streetscape features relevant to physical activity that was developed for international use. This study examined the inter-observer reliability of the instrument in five countries. Methods: MAPS-Global was developed by compiling concepts and items from eight environmental measures relevant to walking and bicycling. Inter-rater reliability data were collected in neighborhoods selected to vary on geographic information system (GIS)-derived macro-level walkability in five countries ...