{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,12]],"date-time":"2026-10-12T21:15:46Z","timestamp":1791839746001,"version":"4.3.4"},"reference-count":45,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,1,5]],"date-time":"2026-01-05T00:00:00Z","timestamp":1767571200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Public Health"],"abstract":"<jats:sec>\n                    <jats:title>Objective<\/jats:title>\n                    <jats:p>Stair ambulation is an essential daily activity associated with maintaining mobility and musculoskeletal health, and its biomechanical characteristics may influence fall risk. This study aimed to examine how different stair-walking strategies\u2014single-step and double-step ascent\u2014affect peri-knee muscle forces and joint loading using OpenSim-based musculoskeletal simulations, thereby providing biomechanical insights for public health\u2013oriented interventions in injury prevention and rehabilitation.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>Synchronized kinematic and kinetic data were imported into OpenSim musculoskeletal models to compute knee joint angles, joint reaction forces, and peri-knee muscle forces. The simulated muscle activation levels were then compared with synchronized surface electromyography (sEMG) signals to validate the reliability of the simulations.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      Results indicated that the double-step stair ascent mode produced significantly greater step length (\n                      <jats:italic>p<\/jats:italic>\n                      \u202f=\u202f0.001) and larger peak hip (\n                      <jats:italic>p<\/jats:italic>\n                      \u202f=\u202f0.002) and knee (\n                      <jats:italic>p<\/jats:italic>\n                      \u202f=\u202f0.015) flexion compared with the single-step mode. Continuous-time SPM analysis further revealed that knee flexion remained significantly higher in the double-step mode throughout most of the single support phase (\n                      <jats:italic>p<\/jats:italic>\n                      \u202f&amp;lt;\u202f0.001), while no significant differences were observed in knee joint reaction forces (\n                      <jats:italic>p<\/jats:italic>\n                      \u202f&amp;gt;\u202f0.05). Muscle force analysis showed that quadriceps muscle force, including the quadriceps components (vastus medialis\/lateralis\/intermedius and rectus femoris) was significantly greater in the double-step mode during the early stage of the single support phase (\n                      <jats:italic>p<\/jats:italic>\n                      \u202f&amp;lt;\u202f0.001). For the hamstrings, only the biceps femoris long head demonstrated significant differences between modes (\n                      <jats:italic>p<\/jats:italic>\n                      \u202f&amp;lt;\u202f0.001), whereas the biceps femoris short head, semimembranosus, semitendinosus, and gastrocnemius showed no significant differences (\n                      <jats:italic>p<\/jats:italic>\n                      \u202f&amp;gt;\u202f0.05).\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>Double-Step Mode increased step length, hip mobility, and quadriceps activation without significantly elevating knee joint forces, supporting knee stability under higher mechanical demands. From a public health perspective, stair walking may enhance lower-limb muscle engagement and potentially contribute to the maintenance of balance control and mobility, while Single-Step Mode may be safer for individuals with knee impairments by minimizing joint stress and supporting rehabilitation.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.3389\/fpubh.2025.1725056","type":"journal-article","created":{"date-parts":[[2026,1,5]],"date-time":"2026-01-05T06:37:55Z","timestamp":1767595075000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":3,"title":["Biomechanical analysis of stair walking patterns and their implications for knee health in young males"],"prefix":"10.3389","volume":"13","author":[{"given":"Yang","family":"Sun","sequence":"first","affiliation":[{"name":"School of Physical Education, Yanshan University","place":["Qinhuangdao, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Qingkang","family":"Mei","sequence":"additional","affiliation":[{"name":"Department of Physical Education, Hebei Institute of Mechanical and Electrical Technology","place":["Xingtai, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Danyang","family":"Kou","sequence":"additional","affiliation":[{"name":"School of Physical Education, Yanshan University","place":["Qinhuangdao, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jiujiang","family":"Liu","sequence":"additional","affiliation":[{"name":"School of Physical Education, Yanshan University","place":["Qinhuangdao, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yi","family":"Yang","sequence":"additional","affiliation":[{"name":"School of Physical Education, Yanshan University","place":["Qinhuangdao, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lian","family":"Duan","sequence":"additional","affiliation":[{"name":"School of Physical Education, Yanshan University","place":["Qinhuangdao, China"]},{"name":"China Volleyball College, Beijing Sport University","place":["Beijing, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yuan","family":"Gao","sequence":"additional","affiliation":[{"name":"School of Physical Education, Yanshan University","place":["Qinhuangdao, China"]},{"name":"Hebei Provincial Key Laboratory of Intelligent Rehabilitation and Neuromodulation, Yanshan University","place":["Qinhuangdao, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2026,1,5]]},"reference":[{"key":"ref1","doi-asserted-by":"publisher","first-page":"1","DOI":"10.1186\/s12891-018-1980-3","article-title":"Objective assessment of physical activity and sedentary behaviour in knee 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