{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,13]],"date-time":"2026-04-13T18:43:35Z","timestamp":1776105815552,"version":"3.50.1"},"reference-count":47,"publisher":"Public Library of Science (PLoS)","issue":"4","license":[{"start":{"date-parts":[[2026,4,13]],"date-time":"2026-04-13T00:00:00Z","timestamp":1776038400000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100000038","name":"Natural Sciences and Engineering Research Council of Canada","doi-asserted-by":"publisher","award":["RGPIN- 2017\u201306790"],"award-info":[{"award-number":["RGPIN- 2017\u201306790"]}],"id":[{"id":"10.13039\/501100000038","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["www.plosone.org"],"crossmark-restriction":false},"short-container-title":["PLoS One"],"abstract":"<jats:p>\n                    Ankle joint quasi-stiffness is a measure representing the control of quiet standing. Here we investigated three methods for determining parameters associated with ankle joint quasi-stiffness. Eleven healthy, young males were asked to stand quietly with eyes open (EO) and eyes closed (EC). Ankle joint quasi-stiffness was computed using two methods, one proposed by Winter et al. (Winter DA, et al. J\n                    <jats:italic>Neurophysiol<\/jats:italic>\n                    80: 1211\u22121221, 1998) (\n                    <jats:inline-formula id=\"pone.0338581.e001\">\n                      <jats:alternatives>\n                        <jats:graphic xmlns:xlink=\"http:\/\/www.w3.org\/1999\/xlink\" id=\"pone.0338581.e001g\" mimetype=\"image\" position=\"anchor\" xlink:href=\"info:doi\/10.1371\/journal.pone.0338581.e001\" xlink:type=\"simple\"\/>\n                        <mml:math xmlns:mml=\"http:\/\/www.w3.org\/1998\/Math\/MathML\" display=\"inline\" id=\"M1\">\n                          <mml:mrow>\n                            <mml:msub>\n                              <mml:mrow>\n                                <mml:mrow>\n                                  <mml:mi>K<\/mml:mi>\n                                <\/mml:mrow>\n                              <\/mml:mrow>\n                              <mml:mrow>\n                                <mml:mrow>\n                                  <mml:mi>q<\/mml:mi>\n                                <\/mml:mrow>\n                                <mml:mrow>\n                                  <mml:mi>s<\/mml:mi>\n                                <\/mml:mrow>\n                                <mml:mrow>\n                                  <mml:mtext>1<\/mml:mtext>\n                                <\/mml:mrow>\n                              <\/mml:mrow>\n                            <\/mml:msub>\n                          <\/mml:mrow>\n                        <\/mml:math>\n                      <\/jats:alternatives>\n                    <\/jats:inline-formula>\n                    ) and another by Loram and Lakie (Loram ID, et al. J Physiol 540: 1111\u22121124, 2002) (\n                    <jats:inline-formula id=\"pone.0338581.e002\">\n                      <jats:alternatives>\n                        <jats:graphic xmlns:xlink=\"http:\/\/www.w3.org\/1999\/xlink\" id=\"pone.0338581.e002g\" mimetype=\"image\" position=\"anchor\" xlink:href=\"info:doi\/10.1371\/journal.pone.0338581.e002\" xlink:type=\"simple\"\/>\n                        <mml:math xmlns:mml=\"http:\/\/www.w3.org\/1998\/Math\/MathML\" display=\"inline\" id=\"M2\">\n                          <mml:mrow>\n                            <mml:msub>\n                              <mml:mrow>\n                                <mml:mrow>\n                                  <mml:mi>K<\/mml:mi>\n                                <\/mml:mrow>\n                              <\/mml:mrow>\n                              <mml:mrow>\n                                <mml:mrow>\n                                  <mml:mi>q<\/mml:mi>\n                                <\/mml:mrow>\n                                <mml:mrow>\n                                  <mml:mi>s<\/mml:mi>\n                                <\/mml:mrow>\n                                <mml:mrow>\n                                  <mml:mtext>2<\/mml:mtext>\n                                <\/mml:mrow>\n                              <\/mml:mrow>\n                            <\/mml:msub>\n                          <\/mml:mrow>\n                        <\/mml:math>\n                      <\/jats:alternatives>\n                    <\/jats:inline-formula>\n                    ). Both values were normalized using participants\u2019 body sizes. The short-term scaling exponent in stabilogram diffusion analysis (\n                    <jats:inline-formula id=\"pone.0338581.e003\">\n                      <jats:alternatives>\n                        <jats:graphic xmlns:xlink=\"http:\/\/www.w3.org\/1999\/xlink\" id=\"pone.0338581.e003g\" mimetype=\"image\" position=\"anchor\" xlink:href=\"info:doi\/10.1371\/journal.pone.0338581.e003\" xlink:type=\"simple\"\/>\n                        <mml:math xmlns:mml=\"http:\/\/www.w3.org\/1998\/Math\/MathML\" display=\"inline\" id=\"M3\">\n                          <mml:mrow>\n                            <mml:msub>\n                              <mml:mrow>\n                                <mml:mrow>\n                                  <mml:mi>H<\/mml:mi>\n                                <\/mml:mrow>\n                              <\/mml:mrow>\n                              <mml:mrow>\n                                <mml:mrow>\n                                  <mml:mi>s<\/mml:mi>\n                                <\/mml:mrow>\n                              <\/mml:mrow>\n                            <\/mml:msub>\n                          <\/mml:mrow>\n                        <\/mml:math>\n                      <\/jats:alternatives>\n                    <\/jats:inline-formula>\n                    ), which has been linked to quasi-stiffness, was applied. A two-way repeated measures ANOVA revealed a significant main effect of methodology (p &lt; 0.0001, partial \u03b7\u00b2 = 0.42), but no significant effect of eye condition (p = 0.1947, partial \u03b7\u00b2 = 0.06), nor interaction effect (p = 0.4742, partial \u03b7\u00b2 = 0.02). Intraclass Correlation Coefficient (ICC(3,1)) analysis indicates good reliability between\n                    <jats:inline-formula id=\"pone.0338581.e004\">\n                      <jats:alternatives>\n                        <jats:graphic xmlns:xlink=\"http:\/\/www.w3.org\/1999\/xlink\" id=\"pone.0338581.e004g\" mimetype=\"image\" position=\"anchor\" xlink:href=\"info:doi\/10.1371\/journal.pone.0338581.e004\" xlink:type=\"simple\"\/>\n                        <mml:math xmlns:mml=\"http:\/\/www.w3.org\/1998\/Math\/MathML\" display=\"inline\" id=\"M4\">\n                          <mml:mrow>\n                            <mml:msub>\n                              <mml:mrow>\n                                <mml:mrow>\n                                  <mml:mi>K<\/mml:mi>\n                                <\/mml:mrow>\n                              <\/mml:mrow>\n                              <mml:mrow>\n                                <mml:mrow>\n                                  <mml:mi>q<\/mml:mi>\n                                <\/mml:mrow>\n                                <mml:mrow>\n                                  <mml:mi>s<\/mml:mi>\n                                <\/mml:mrow>\n                                <mml:mrow>\n                                  <mml:mtext>1<\/mml:mtext>\n                                <\/mml:mrow>\n                              <\/mml:mrow>\n                            <\/mml:msub>\n                          <\/mml:mrow>\n                        <\/mml:math>\n                      <\/jats:alternatives>\n                    <\/jats:inline-formula>\n                    and\n                    <jats:inline-formula id=\"pone.0338581.e005\">\n                      <jats:alternatives>\n                        <jats:graphic xmlns:xlink=\"http:\/\/www.w3.org\/1999\/xlink\" id=\"pone.0338581.e005g\" mimetype=\"image\" position=\"anchor\" xlink:href=\"info:doi\/10.1371\/journal.pone.0338581.e005\" xlink:type=\"simple\"\/>\n                        <mml:math xmlns:mml=\"http:\/\/www.w3.org\/1998\/Math\/MathML\" display=\"inline\" id=\"M5\">\n                          <mml:mrow>\n                            <mml:msub>\n                              <mml:mrow>\n                                <mml:mrow>\n                                  <mml:mi>K<\/mml:mi>\n                                <\/mml:mrow>\n                              <\/mml:mrow>\n                              <mml:mrow>\n                                <mml:mrow>\n                                  <mml:mi>q<\/mml:mi>\n                                <\/mml:mrow>\n                                <mml:mrow>\n                                  <mml:mi>s<\/mml:mi>\n                                <\/mml:mrow>\n                                <mml:mrow>\n                                  <mml:mtext>2<\/mml:mtext>\n                                <\/mml:mrow>\n                              <\/mml:mrow>\n                            <\/mml:msub>\n                          <\/mml:mrow>\n                        <\/mml:math>\n                      <\/jats:alternatives>\n                    <\/jats:inline-formula>\n                    with an ICC value of 0.858 (p &lt; 0.001) in the EO condition, and moderate reliability with an ICC value of 0.718 (p = 0.004) in the EC condition.\n                    <jats:inline-formula id=\"pone.0338581.e006\">\n                      <jats:alternatives>\n                        <jats:graphic xmlns:xlink=\"http:\/\/www.w3.org\/1999\/xlink\" id=\"pone.0338581.e006g\" mimetype=\"image\" position=\"anchor\" xlink:href=\"info:doi\/10.1371\/journal.pone.0338581.e006\" xlink:type=\"simple\"\/>\n                        <mml:math xmlns:mml=\"http:\/\/www.w3.org\/1998\/Math\/MathML\" display=\"inline\" id=\"M6\">\n                          <mml:mrow>\n                            <mml:msub>\n                              <mml:mrow>\n                                <mml:mrow>\n                                  <mml:mi>H<\/mml:mi>\n                                <\/mml:mrow>\n                              <\/mml:mrow>\n                              <mml:mrow>\n                                <mml:mrow>\n                                  <mml:mi>s<\/mml:mi>\n                                <\/mml:mrow>\n                              <\/mml:mrow>\n                            <\/mml:msub>\n                          <\/mml:mrow>\n                        <\/mml:math>\n                      <\/jats:alternatives>\n                    <\/jats:inline-formula>\n                    and\n                    <jats:inline-formula id=\"pone.0338581.e007\">\n                      <jats:alternatives>\n                        <jats:graphic xmlns:xlink=\"http:\/\/www.w3.org\/1999\/xlink\" id=\"pone.0338581.e007g\" mimetype=\"image\" position=\"anchor\" xlink:href=\"info:doi\/10.1371\/journal.pone.0338581.e007\" xlink:type=\"simple\"\/>\n                        <mml:math xmlns:mml=\"http:\/\/www.w3.org\/1998\/Math\/MathML\" display=\"inline\" id=\"M7\">\n                          <mml:mrow>\n                            <mml:msub>\n                              <mml:mrow>\n                                <mml:mrow>\n                                  <mml:mi>K<\/mml:mi>\n                                <\/mml:mrow>\n                              <\/mml:mrow>\n                              <mml:mrow>\n                                <mml:mrow>\n                                  <mml:mi>q<\/mml:mi>\n                                <\/mml:mrow>\n                                <mml:mrow>\n                                  <mml:mi>s<\/mml:mi>\n                                <\/mml:mrow>\n                                <mml:mrow>\n                                  <mml:mtext>1<\/mml:mtext>\n                                <\/mml:mrow>\n                              <\/mml:mrow>\n                            <\/mml:msub>\n                          <\/mml:mrow>\n                        <\/mml:math>\n                      <\/jats:alternatives>\n                    <\/jats:inline-formula>\n                    exhibited a very strong negative correlation in the EO (\n                    <jats:inline-formula id=\"pone.0338581.e008\">\n                      <jats:alternatives>\n                        <jats:graphic xmlns:xlink=\"http:\/\/www.w3.org\/1999\/xlink\" id=\"pone.0338581.e008g\" mimetype=\"image\" position=\"anchor\" xlink:href=\"info:doi\/10.1371\/journal.pone.0338581.e008\" xlink:type=\"simple\"\/>\n                        <mml:math xmlns:mml=\"http:\/\/www.w3.org\/1998\/Math\/MathML\" display=\"inline\" id=\"M8\">\n                          <mml:mrow>\n                            <mml:mrow>\n                              <mml:mi>\u03c1<\/mml:mi>\n                            <\/mml:mrow>\n                          <\/mml:mrow>\n                        <\/mml:math>\n                      <\/jats:alternatives>\n                    <\/jats:inline-formula>\n                    = \u22120.909) condition and a moderately strong negative correlation in the EC (\n                    <jats:inline-formula id=\"pone.0338581.e009\">\n                      <jats:alternatives>\n                        <jats:graphic xmlns:xlink=\"http:\/\/www.w3.org\/1999\/xlink\" id=\"pone.0338581.e009g\" mimetype=\"image\" position=\"anchor\" xlink:href=\"info:doi\/10.1371\/journal.pone.0338581.e009\" xlink:type=\"simple\"\/>\n                        <mml:math xmlns:mml=\"http:\/\/www.w3.org\/1998\/Math\/MathML\" display=\"inline\" id=\"M9\">\n                          <mml:mrow>\n                            <mml:mrow>\n                              <mml:mi>\u03c1<\/mml:mi>\n                            <\/mml:mrow>\n                          <\/mml:mrow>\n                        <\/mml:math>\n                      <\/jats:alternatives>\n                    <\/jats:inline-formula>\n                    = \u22120.782) condition.\n                    <jats:inline-formula id=\"pone.0338581.e010\">\n                      <jats:alternatives>\n                        <jats:graphic xmlns:xlink=\"http:\/\/www.w3.org\/1999\/xlink\" id=\"pone.0338581.e010g\" mimetype=\"image\" position=\"anchor\" xlink:href=\"info:doi\/10.1371\/journal.pone.0338581.e010\" xlink:type=\"simple\"\/>\n                        <mml:math xmlns:mml=\"http:\/\/www.w3.org\/1998\/Math\/MathML\" display=\"inline\" id=\"M10\">\n                          <mml:mrow>\n                            <mml:msub>\n                              <mml:mrow>\n                                <mml:mrow>\n                                  <mml:mi>H<\/mml:mi>\n                                <\/mml:mrow>\n                              <\/mml:mrow>\n                              <mml:mrow>\n                                <mml:mrow>\n                                  <mml:mi>s<\/mml:mi>\n                                <\/mml:mrow>\n                              <\/mml:mrow>\n                            <\/mml:msub>\n                          <\/mml:mrow>\n                        <\/mml:math>\n                      <\/jats:alternatives>\n                    <\/jats:inline-formula>\n                    and\n                    <jats:inline-formula id=\"pone.0338581.e011\">\n                      <jats:alternatives>\n                        <jats:graphic xmlns:xlink=\"http:\/\/www.w3.org\/1999\/xlink\" id=\"pone.0338581.e011g\" mimetype=\"image\" position=\"anchor\" xlink:href=\"info:doi\/10.1371\/journal.pone.0338581.e011\" xlink:type=\"simple\"\/>\n                        <mml:math xmlns:mml=\"http:\/\/www.w3.org\/1998\/Math\/MathML\" display=\"inline\" id=\"M11\">\n                          <mml:mrow>\n                            <mml:msub>\n                              <mml:mrow>\n                                <mml:mrow>\n                                  <mml:mi>K<\/mml:mi>\n                                <\/mml:mrow>\n                              <\/mml:mrow>\n                              <mml:mrow>\n                                <mml:mrow>\n                                  <mml:mi>q<\/mml:mi>\n                                <\/mml:mrow>\n                                <mml:mrow>\n                                  <mml:mi>s<\/mml:mi>\n                                <\/mml:mrow>\n                                <mml:mrow>\n                                  <mml:mtext>2<\/mml:mtext>\n                                <\/mml:mrow>\n                              <\/mml:mrow>\n                            <\/mml:msub>\n                          <\/mml:mrow>\n                        <\/mml:math>\n                      <\/jats:alternatives>\n                    <\/jats:inline-formula>\n                    exhibited moderately strong negative correlation in both the EO (\n                    <jats:inline-formula id=\"pone.0338581.e012\">\n                      <jats:alternatives>\n                        <jats:graphic xmlns:xlink=\"http:\/\/www.w3.org\/1999\/xlink\" id=\"pone.0338581.e012g\" mimetype=\"image\" position=\"anchor\" xlink:href=\"info:doi\/10.1371\/journal.pone.0338581.e012\" xlink:type=\"simple\"\/>\n                        <mml:math xmlns:mml=\"http:\/\/www.w3.org\/1998\/Math\/MathML\" display=\"inline\" id=\"M12\">\n                          <mml:mrow>\n                            <mml:mrow>\n                              <mml:mi>\u03c1<\/mml:mi>\n                            <\/mml:mrow>\n                          <\/mml:mrow>\n                        <\/mml:math>\n                      <\/jats:alternatives>\n                    <\/jats:inline-formula>\n                    = \u22120.664) and EC (\n                    <jats:inline-formula id=\"pone.0338581.e013\">\n                      <jats:alternatives>\n                        <jats:graphic xmlns:xlink=\"http:\/\/www.w3.org\/1999\/xlink\" id=\"pone.0338581.e013g\" mimetype=\"image\" position=\"anchor\" xlink:href=\"info:doi\/10.1371\/journal.pone.0338581.e013\" xlink:type=\"simple\"\/>\n                        <mml:math xmlns:mml=\"http:\/\/www.w3.org\/1998\/Math\/MathML\" display=\"inline\" id=\"M13\">\n                          <mml:mrow>\n                            <mml:mrow>\n                              <mml:mi>\u03c1<\/mml:mi>\n                            <\/mml:mrow>\n                          <\/mml:mrow>\n                        <\/mml:math>\n                      <\/jats:alternatives>\n                    <\/jats:inline-formula>\n                    = \u22120.555) conditions. The good and moderate reliability between\n                    <jats:inline-formula id=\"pone.0338581.e014\">\n                      <jats:alternatives>\n                        <jats:graphic xmlns:xlink=\"http:\/\/www.w3.org\/1999\/xlink\" id=\"pone.0338581.e014g\" mimetype=\"image\" position=\"anchor\" xlink:href=\"info:doi\/10.1371\/journal.pone.0338581.e014\" xlink:type=\"simple\"\/>\n                        <mml:math xmlns:mml=\"http:\/\/www.w3.org\/1998\/Math\/MathML\" display=\"inline\" id=\"M14\">\n                          <mml:mrow>\n                            <mml:msub>\n                              <mml:mrow>\n                                <mml:mrow>\n                                  <mml:mi>K<\/mml:mi>\n                                <\/mml:mrow>\n                              <\/mml:mrow>\n                              <mml:mrow>\n                                <mml:mrow>\n                                  <mml:mi>q<\/mml:mi>\n                                <\/mml:mrow>\n                                <mml:mrow>\n                                  <mml:mi>s<\/mml:mi>\n                                <\/mml:mrow>\n                                <mml:mrow>\n                                  <mml:mtext>1<\/mml:mtext>\n                                <\/mml:mrow>\n                              <\/mml:mrow>\n                            <\/mml:msub>\n                          <\/mml:mrow>\n                        <\/mml:math>\n                      <\/jats:alternatives>\n                    <\/jats:inline-formula>\n                    and\n                    <jats:inline-formula id=\"pone.0338581.e015\">\n                      <jats:alternatives>\n                        <jats:graphic xmlns:xlink=\"http:\/\/www.w3.org\/1999\/xlink\" id=\"pone.0338581.e015g\" mimetype=\"image\" position=\"anchor\" xlink:href=\"info:doi\/10.1371\/journal.pone.0338581.e015\" xlink:type=\"simple\"\/>\n                        <mml:math xmlns:mml=\"http:\/\/www.w3.org\/1998\/Math\/MathML\" display=\"inline\" id=\"M15\">\n                          <mml:mrow>\n                            <mml:msub>\n                              <mml:mrow>\n                                <mml:mrow>\n                                  <mml:mi>K<\/mml:mi>\n                                <\/mml:mrow>\n                              <\/mml:mrow>\n                              <mml:mrow>\n                                <mml:mrow>\n                                  <mml:mi>q<\/mml:mi>\n                                <\/mml:mrow>\n                                <mml:mrow>\n                                  <mml:mi>s<\/mml:mi>\n                                <\/mml:mrow>\n                                <mml:mrow>\n                                  <mml:mtext>2<\/mml:mtext>\n                                <\/mml:mrow>\n                              <\/mml:mrow>\n                            <\/mml:msub>\n                          <\/mml:mrow>\n                        <\/mml:math>\n                      <\/jats:alternatives>\n                    <\/jats:inline-formula>\n                    suggests that both measures capture similar stiffness attributes relating to their neuro-mechanical components, despite a significant methodological difference. Additionally, relatively high correlations of\n                    <jats:inline-formula id=\"pone.0338581.e016\">\n                      <jats:alternatives>\n                        <jats:graphic xmlns:xlink=\"http:\/\/www.w3.org\/1999\/xlink\" id=\"pone.0338581.e016g\" mimetype=\"image\" position=\"anchor\" xlink:href=\"info:doi\/10.1371\/journal.pone.0338581.e016\" xlink:type=\"simple\"\/>\n                        <mml:math xmlns:mml=\"http:\/\/www.w3.org\/1998\/Math\/MathML\" display=\"inline\" id=\"M16\">\n                          <mml:mrow>\n                            <mml:msub>\n                              <mml:mrow>\n                                <mml:mrow>\n                                  <mml:mi>H<\/mml:mi>\n                                <\/mml:mrow>\n                              <\/mml:mrow>\n                              <mml:mrow>\n                                <mml:mrow>\n                                  <mml:mi>s<\/mml:mi>\n                                <\/mml:mrow>\n                              <\/mml:mrow>\n                            <\/mml:msub>\n                          <\/mml:mrow>\n                        <\/mml:math>\n                      <\/jats:alternatives>\n                    <\/jats:inline-formula>\n                    with\n                    <jats:inline-formula id=\"pone.0338581.e017\">\n                      <jats:alternatives>\n                        <jats:graphic xmlns:xlink=\"http:\/\/www.w3.org\/1999\/xlink\" id=\"pone.0338581.e017g\" mimetype=\"image\" position=\"anchor\" xlink:href=\"info:doi\/10.1371\/journal.pone.0338581.e017\" xlink:type=\"simple\"\/>\n                        <mml:math xmlns:mml=\"http:\/\/www.w3.org\/1998\/Math\/MathML\" display=\"inline\" id=\"M17\">\n                          <mml:mrow>\n                            <mml:msub>\n                              <mml:mrow>\n                                <mml:mrow>\n                                  <mml:mi>K<\/mml:mi>\n                                <\/mml:mrow>\n                              <\/mml:mrow>\n                              <mml:mrow>\n                                <mml:mrow>\n                                  <mml:mi>q<\/mml:mi>\n                                <\/mml:mrow>\n                                <mml:mrow>\n                                  <mml:mi>s<\/mml:mi>\n                                <\/mml:mrow>\n                                <mml:mrow>\n                                  <mml:mtext>1<\/mml:mtext>\n                                <\/mml:mrow>\n                              <\/mml:mrow>\n                            <\/mml:msub>\n                            <mml:mtext>\u00a0<\/mml:mtext>\n                          <\/mml:mrow>\n                        <\/mml:math>\n                      <\/jats:alternatives>\n                    <\/jats:inline-formula>\n                    and with\n                    <jats:inline-formula id=\"pone.0338581.e018\">\n                      <jats:alternatives>\n                        <jats:graphic xmlns:xlink=\"http:\/\/www.w3.org\/1999\/xlink\" id=\"pone.0338581.e018g\" mimetype=\"image\" position=\"anchor\" xlink:href=\"info:doi\/10.1371\/journal.pone.0338581.e018\" xlink:type=\"simple\"\/>\n                        <mml:math xmlns:mml=\"http:\/\/www.w3.org\/1998\/Math\/MathML\" display=\"inline\" id=\"M18\">\n                          <mml:mrow>\n                            <mml:msub>\n                              <mml:mrow>\n                                <mml:mrow>\n                                  <mml:mi>K<\/mml:mi>\n                                <\/mml:mrow>\n                              <\/mml:mrow>\n                              <mml:mrow>\n                                <mml:mrow>\n                                  <mml:mi>q<\/mml:mi>\n                                <\/mml:mrow>\n                                <mml:mrow>\n                                  <mml:mi>s<\/mml:mi>\n                                <\/mml:mrow>\n                                <mml:mrow>\n                                  <mml:mtext>2<\/mml:mtext>\n                                <\/mml:mrow>\n                              <\/mml:mrow>\n                            <\/mml:msub>\n                          <\/mml:mrow>\n                        <\/mml:math>\n                      <\/jats:alternatives>\n                    <\/jats:inline-formula>\n                    suggest that the stochastic characteristics of centre of pressure in the short period indeed reflect the overall quasi-stiffness at the ankle joint.\n                  <\/jats:p>","DOI":"10.1371\/journal.pone.0338581","type":"journal-article","created":{"date-parts":[[2026,4,13]],"date-time":"2026-04-13T17:23:16Z","timestamp":1776100996000},"page":"e0338581","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":0,"title":["Comparison of methods for determining parameters related to ankle joint quasi-stiffness during quiet standing"],"prefix":"10.1371","volume":"21","author":[{"given":"Kaylie","family":"Lau","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6229-5735","authenticated-orcid":true,"given":"Kai Lon","family":"Fok","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jonguk","family":"Lee","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0207-3241","authenticated-orcid":true,"given":"Kei","family":"Masani","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"340","published-online":{"date-parts":[[2026,4,13]]},"reference":[{"issue":"3","key":"pone.0338581.ref001","doi-asserted-by":"crossref","first-page":"915","DOI":"10.1111\/j.1469-7793.1999.915ad.x","article-title":"Feedforward ankle 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