{"id":{"repo_id":"vt","oai_identifier":"oai:vtechworks.lib.vt.edu:10919/32752"},"canonical_url":"https://search.dev.ndltd.org/etd/vt/oai:vtechworks.lib.vt.edu:10919/32752","repository":{"repo_id":"vt","name":"Virginia Tech","base_url":"https://vtechworks.lib.vt.edu/oai/request"},"display":{"title":"Pushing/Pulling Exertions Disturb Trunk Postural Stability","abstract":"The stability of the spine can be estimated from kinematic variability and nonlinear analyses of seated balance tasks. However, processing methods require sufficient signal duration and test-retest experiments require that the assessment must be reliable. Our goal was to characterize the reliability and establish the trial duration for spine stability assessment. Stationarity, kinematic variability and nonlinear dynamic stability were quantified from kinetic and kinematic data collected during balance performance. Stationarity results showed that a minimum 30 seconds test duration is necessary. Intra-session reliability was excellent, however inter-session reliability needed more test trials to achieve excellent reliability. Few studies have investigated the spinal stability during pushing and pulling exertions. Past studies suggest that the spine can be stabilized by paraspinal muscle stiffness as well as reflexes. We hypothesized that the stability of the spine decreases with exertion force and decreases during pushing more than during pulling exertion. Kinematic variability and nonlinear dynamic stability measurements were quantified from the balance performance during isometric pushing and pulling tasks. Results demonstrated that spinal stability decreased with exertion force and decreased a greater amount during pushing task than during pulling task. Stiffness alone may be insufficient to stabilize the trunk. Results may be able to be explained by slower reflex delay. The results suggested that pushing and pulling exertions have a potential risk of low-back disorders.","abstract_html":"The stability of the spine can be estimated from kinematic variability and nonlinear analyses of seated balance tasks. However, processing methods require sufficient signal duration and test-retest experiments require that the assessment must be reliable. Our goal was to characterize the reliability and establish the trial duration for spine stability assessment. Stationarity, kinematic variability and nonlinear dynamic stability were quantified from kinetic and kinematic data collected during balance performance. Stationarity results showed that a minimum 30 seconds test duration is necessary. Intra-session reliability was excellent, however inter-session reliability needed more test trials to achieve excellent reliability. Few studies have investigated the spinal stability during pushing and pulling exertions. Past studies suggest that the spine can be stabilized by paraspinal muscle stiffness as well as reflexes. We hypothesized that the stability of the spine decreases with exertion force and decreases during pushing more than during pulling exertion. Kinematic variability and nonlinear dynamic stability measurements were quantified from the balance performance during isometric pushing and pulling tasks. Results demonstrated that spinal stability decreased with exertion force and decreased a greater amount during pushing task than during pulling task. Stiffness alone may be insufficient to stabilize the trunk. Results may be able to be explained by slower reflex delay. The results suggested that pushing and pulling exertions have a potential risk of low-back disorders.","abstract_has_math":false,"creators":["Lee, HyunWook"],"institution":"Virginia Tech","degree_name":"Master of Science","degree_level":"masters","degree_discipline":"Biomedical Engineering and Sciences","degree_department":"Biomedical Engineering and Sciences","school":null,"contributors":[],"advisors":[],"committee_chairs":["Granata, Kevin P.","Madigan, Michael L."],"committee_members":["Hong, Dennis W.","Gabler, Hampton Clay"],"year":2007,"date_issued":"2007-05-08","date_published":"2007-05-08","updated_at":"2026-07-22T22:18:49Z","subjects":["Pushing/Pulling","Stability","Stationarity","Reflex","Reliability","Low-Back","Spine"],"languages":[],"rights":["In Copyright"],"rights_urls":["http://rightsstatements.org/vocab/InC/1.0/"],"identifier_entries":[{"key":"dc:identifier.other","label":"Dc Identifier Other","values":["etd-05142007-103426"],"render_values":[{"text":"etd-05142007-103426","href":null,"code":true}]}]},"links":{"outbound_url":"http://hdl.handle.net/10919/32752","outbound_label":"Handle","outbound_source":"dc:identifier.uri"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor.committeechair","label":"Committee Chair","values":["Granata, Kevin P.","Madigan, Michael L."]},{"key":"dc:contributor.committeemember","label":"Committee Member","values":["Hong, Dennis W.","Gabler, Hampton Clay"]},{"key":"dc:contributor.department","label":"Department","values":["Biomedical Engineering and Sciences"]},{"key":"dc:creator","label":"Author","values":["Lee, HyunWook"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.accessioned","label":"Dc Date Accessioned","values":["2014-03-14T20:36:47Z"]},{"key":"dc:date.available","label":"Dc Date Available","values":["2014-03-14T20:36:47Z","2007-08-13"]},{"key":"dc:date.issued","label":"Date","values":["2007-05-08"]},{"key":"dc:publisher","label":"Institution","values":["Virginia Tech"]},{"key":"dc:type","label":"Dc Type","values":["Thesis"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Biomedical Engineering and Sciences"]},{"key":"thesis:degree_level","label":"Degree Level","values":["masters"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Master of Science"]},{"key":"thesis:institution_name","label":"Thesis Institution Name","values":["Virginia Polytechnic Institute and State University"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Pushing/Pulling","Stability","Stationarity","Reflex","Reliability","Low-Back","Spine"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:rights","label":"Dc Rights","values":["In Copyright"]},{"key":"dc:rights.uri","label":"Rights URI","values":["http://rightsstatements.org/vocab/InC/1.0/"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier.other","label":"Dc Identifier Other","values":["etd-05142007-103426"]},{"key":"dc:identifier.uri","label":"Identifier URI","values":["http://hdl.handle.net/10919/32752"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["The stability of the spine can be estimated from kinematic variability and nonlinear analyses of seated balance tasks. However, processing methods require sufficient signal duration and test-retest experiments require that the assessment must be reliable. Our goal was to characterize the reliability and establish the trial duration for spine stability assessment. Stationarity, kinematic variability and nonlinear dynamic stability were quantified from kinetic and kinematic data collected during balance performance. Stationarity results showed that a minimum 30 seconds test duration is necessary. Intra-session reliability was excellent, however inter-session reliability needed more test trials to achieve excellent reliability. Few studies have investigated the spinal stability during pushing and pulling exertions. Past studies suggest that the spine can be stabilized by paraspinal muscle stiffness as well as reflexes. We hypothesized that the stability of the spine decreases with exertion force and decreases during pushing more than during pulling exertion. Kinematic variability and nonlinear dynamic stability measurements were quantified from the balance performance during isometric pushing and pulling tasks. Results demonstrated that spinal stability decreased with exertion force and decreased a greater amount during pushing task than during pulling task. Stiffness alone may be insufficient to stabilize the trunk. Results may be able to be explained by slower reflex delay. The results suggested that pushing and pulling exertions have a potential risk of low-back disorders."]},{"key":"dc:description.degree","label":"Dc Description Degree","values":["Master of Science"]},{"key":"dc:title","label":"Title","values":["Pushing/Pulling Exertions Disturb Trunk Postural Stability"]}]}],"canonical_facts":{"dc:contributor.committeechair":["Granata, Kevin P.","Madigan, Michael L."],"dc:contributor.committeemember":["Hong, Dennis W.","Gabler, Hampton Clay"],"dc:contributor.department":["Biomedical Engineering and Sciences"],"dc:creator":["Lee, HyunWook"],"dc:date.accessioned":["2014-03-14T20:36:47Z"],"dc:date.available":["2014-03-14T20:36:47Z","2007-08-13"],"dc:date.issued":["2007-05-08"],"dc:description.abstract":["The stability of the spine can be estimated from kinematic variability and nonlinear analyses of seated balance tasks. However, processing methods require sufficient signal duration and test-retest experiments require that the assessment must be reliable. Our goal was to characterize the reliability and establish the trial duration for spine stability assessment. Stationarity, kinematic variability and nonlinear dynamic stability were quantified from kinetic and kinematic data collected during balance performance. Stationarity results showed that a minimum 30 seconds test duration is necessary. Intra-session reliability was excellent, however inter-session reliability needed more test trials to achieve excellent reliability. Few studies have investigated the spinal stability during pushing and pulling exertions. Past studies suggest that the spine can be stabilized by paraspinal muscle stiffness as well as reflexes. We hypothesized that the stability of the spine decreases with exertion force and decreases during pushing more than during pulling exertion. Kinematic variability and nonlinear dynamic stability measurements were quantified from the balance performance during isometric pushing and pulling tasks. Results demonstrated that spinal stability decreased with exertion force and decreased a greater amount during pushing task than during pulling task. Stiffness alone may be insufficient to stabilize the trunk. Results may be able to be explained by slower reflex delay. The results suggested that pushing and pulling exertions have a potential risk of low-back disorders."],"dc:description.degree":["Master of Science"],"dc:identifier.other":["etd-05142007-103426"],"dc:identifier.uri":["http://hdl.handle.net/10919/32752"],"dc:publisher":["Virginia Tech"],"dc:rights":["In Copyright"],"dc:rights.uri":["http://rightsstatements.org/vocab/InC/1.0/"],"dc:subject":["Pushing/Pulling","Stability","Stationarity","Reflex","Reliability","Low-Back","Spine"],"dc:title":["Pushing/Pulling Exertions Disturb Trunk Postural Stability"],"dc:type":["Thesis"],"thesis:degree_discipline":["Biomedical Engineering and Sciences"],"thesis:degree_level":["masters"],"thesis:degree_name":["Master of Science"],"thesis:institution_name":["Virginia Polytechnic Institute and State University"]},"updated_at":"2026-07-22T22:18:49Z"}