{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,24]],"date-time":"2026-10-24T01:32:16Z","timestamp":1792805536445,"version":"4.5.0"},"reference-count":27,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2025,2,6]],"date-time":"2025-02-06T00:00:00Z","timestamp":1738800000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"The National Research Foundation of Korea (NRF), grant funded by the Korean government (MSIT)","award":["RS-2022-NR074290"],"award-info":[{"award-number":["RS-2022-NR074290"]}],"id":[{"id":"https:\/\/ror.org\/013aysd81","id-type":"ROR","asserted-by":"crossref"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Medicina"],"abstract":"<jats:p>Background and Objectives: Weight-bearing activities exacerbate pain and fatigue in functional flat foot, with uphill walking presenting additional challenges due to increased external loads. The current study investigates whether 3D-printed customized arch-support insoles can enhance gait variables and ankle alignment during uphill walking. Materials and Methods: Twenty healthy young adults, divided into two groups (normal foot condition (control, n = 10), functional flat foot (FF, n = 10)), walked on a treadmill at a 10% incline under two conditions: wearing shoes alone (shoe) or wearing shoes with 3D-printed customized arch-support insoles (SI). Gait pattern, center of force (COF), and ankle joint angles were analyzed by OptoGait, Tekscan, and Kinovea, respectively. Results: The foot flat phase of the gait pattern was prolonged in individuals with FF compared to the control under both shoe and SI conditions, whereas the propulsive phase was shortened with the SI. Medial deviation of the COF during the propulsive phase, observed in individuals with FF under the shoe condition, was corrected to a more lateral alignment with the SI, resembling the COF alignment of the control. Additionally, individuals with FF under the shoe condition exhibited increased ankle pronation compared to the control, whereas the SI moderated pronation, achieving alignment closer to that of the control. Conclusions: These findings indicate that the 3D-printed customized arch-support insoles can improve gait mechanics and ankle alignment in individuals with FF, particularly under challenging conditions such as uphill walking.<\/jats:p>","DOI":"10.3390\/medicina61020281","type":"journal-article","created":{"date-parts":[[2025,2,6]],"date-time":"2025-02-06T08:53:41Z","timestamp":1738832021000},"page":"281","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["3D-Printed Customized Arch-Support Insoles Improve Gait Mechanics and Ankle Alignment in Young Adults with Functional Flat Foot During Uphill Walking"],"prefix":"10.3390","volume":"61","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-1632-3448","authenticated-orcid":false,"given":"Sanghee","family":"Park","sequence":"first","affiliation":[{"name":"Department of Exercise Rehabilitation, Gachon University, Incheon 21936, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3687-7096","authenticated-orcid":false,"given":"Jin-Hwa","family":"Jung","sequence":"additional","affiliation":[{"name":"Department of Occupational Therapy, Semyung University, Jecheon 27136, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shi","family":"Lei","sequence":"additional","affiliation":[{"name":"Department of Physical Therapy, Gachon University, Incheon 21936, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Eui-Young","family":"Jung","sequence":"additional","affiliation":[{"name":"Department of Physical Therapy, Gachon University, Incheon 21936, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0465-9665","authenticated-orcid":false,"given":"Hwi-Young","family":"Cho","sequence":"additional","affiliation":[{"name":"Department of Physical Therapy, Gachon University, Incheon 21936, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,2,6]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"116","DOI":"10.2106\/00004623-194830010-00013","article-title":"Hypermobile flat-foot with short tendo achillis","volume":"30A","author":"Harris","year":"1948","journal-title":"J. Bone Jt. Surg. Am."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"456","DOI":"10.1177\/107110079902000711","article-title":"Defining flatfoot","volume":"20","author":"Tareco","year":"1999","journal-title":"Foot Ankle Int."},{"key":"ref_3","first-page":"443","article-title":"The Relationship between the Flexible Flatfoot and Plantar Fasciitis: Ultrasonographic Evaluation","volume":"27","author":"Huang","year":"2004","journal-title":"Chang Gung Med. J."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"629","DOI":"10.1177\/107110070202300708","article-title":"The injury risk associated with pes planus in athletes","volume":"23","author":"Michelson","year":"2002","journal-title":"Foot Ankle Int."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"700","DOI":"10.2519\/jospt.2013.4225","article-title":"Association between foot type and lower extremity injuries: Systematic literature review with meta-analysis","volume":"43","author":"Tong","year":"2013","journal-title":"J. Orthop. Sports Phys. Ther."},{"key":"ref_6","doi-asserted-by":"crossref","unstructured":"Lin, K.-W., Chou, L.-W., Su, Y.-T., Wei, S.-H., Chen, C.-S., Lin, K.-W., Chou, L.-W., Su, Y.-T., Wei, S.-H., and Chen, C.-S. (2021). Biomechanical Effect of 3D-Printed Foot Orthoses in Patients with Knee Osteoarthritis. Appl. Sci., 11.","DOI":"10.3390\/app11094200"},{"key":"ref_7","doi-asserted-by":"crossref","unstructured":"Hsu, C.Y., Wang, C.S., Lin, K.W., Chien, M.J., Wei, S.H., and Chen, C.S. (2022). Biomechanical Analysis of the FlatFoot with Different 3D-Printed Insoles on the Lower Extremities. Bioengineering, 9.","DOI":"10.3390\/bioengineering9100563"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"353","DOI":"10.1016\/j.apmr.2004.03.031","article-title":"A 3-dimensional finite element model of the human foot and ankle for insole design","volume":"86","author":"Cheung","year":"2005","journal-title":"Arch. Phys. Med. Rehabil."},{"key":"ref_9","doi-asserted-by":"crossref","unstructured":"Li, L., Yang, L., Yu, F., Shi, J., Zhu, L., Yang, X., Teng, H., Wang, X., and Jiang, Q. (2018). 3D printing individualized heel cup for improving the self-reported pain of plantar fasciitis. J. Transl. Med., 16.","DOI":"10.1186\/s12967-018-1547-y"},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"2081","DOI":"10.1016\/j.jbiomech.2009.06.015","article-title":"The influence of footwear on foot motion during walking and running","volume":"42","author":"Morio","year":"2009","journal-title":"J. Biomech."},{"key":"ref_11","doi-asserted-by":"crossref","unstructured":"Huang, Y.P., Peng, H.T., Wang, X., Chen, Z.R., and Song, C.Y. (2020). The arch support insoles show benefits to people with flatfoot on stance time, cadence, plantar pressure and contact area. PLoS ONE, 15.","DOI":"10.1371\/journal.pone.0237382"},{"key":"ref_12","doi-asserted-by":"crossref","unstructured":"Shin, J.Y., Ryu, Y.U., and Yi, C.W. (2016). Effects of insoles contact on static balance. J. Phys. Ther. Sci., 28.","DOI":"10.1589\/jpts.28.1241"},{"key":"ref_13","doi-asserted-by":"crossref","unstructured":"Schmitt, A.P.L., Liebau, K.H., Hamm, A., Hacke, C., Mittelmeier, W., and Schulze, C. (2022). Comparison of the influence of supportive and sensorimotor insoles in the muscle activity of tibialis anterior and peroneus longus in combat boots. Foot, 52.","DOI":"10.1016\/j.foot.2022.101910"},{"key":"ref_14","doi-asserted-by":"crossref","unstructured":"Peng, Y., Wong, D.W.C., Wang, Y., Chen, T.L.W., Tan, Q., Chen, Z., Jin, Z., and Zhang, M. (2020). Immediate Effects of Medially Posted Insoles on Lower Limb Joint Contact Forces in Adult Acquired Flatfoot: A Pilot Study. Int. J. Environ. Res. Public Health, 17.","DOI":"10.3390\/ijerph17072226"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"4063","DOI":"10.3233\/THC-231785","article-title":"Comparative study of the effects of custom-made insole and ordinary insole in adults with flexible flatfoot on different slopes","volume":"32","author":"Jiang","year":"2024","journal-title":"Technol. Health Care"},{"key":"ref_16","doi-asserted-by":"crossref","unstructured":"Yang, Z., Liu, F., Cui, L., Liu, H., Zuo, J., Liu, L., and Li, S. (2020). Adult rigid flatfoot: Triple arthrodesis and osteotomy. Medicina, 99.","DOI":"10.1097\/MD.0000000000018826"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"649","DOI":"10.3233\/BMR-210069","article-title":"The effects of calf muscles fatigue on dynamic plantar pressure distribution in normal foot posture and flexible flatfoot: A case-control study","volume":"35","author":"Kirmizi","year":"2022","journal-title":"J. Back Musculoskelet. Rehabil."},{"key":"ref_18","doi-asserted-by":"crossref","unstructured":"Iskandar, M.N.S., Loh, R.B.C., Ho, M.Y.M., Pan, J.W., and Kong, P.W. (2023). Crossover gait in running and measuring foot inversion angle at initial foot strike: A front-view video analysis approach. Front. Bioeng. Biotechnol., 11.","DOI":"10.3389\/fbioe.2023.1210049"},{"key":"ref_19","doi-asserted-by":"crossref","unstructured":"Shi, L., Ye, X., Han, D., Yang, C., and Tu, Y. (2023). Acute Effects of Back Squat Combined with Different Elastic Band Resistance on Vertical Jump Performance in Collegiate Basketball Players. J. Sports Sci. Med., 22.","DOI":"10.52082\/jssm.2023.502"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"362","DOI":"10.1016\/j.cmet.2010.08.016","article-title":"Branched-chain amino acid supplementation promotes survival and supports cardiac and skeletal muscle mitochondrial biogenesis in middle-aged mice","volume":"12","author":"Ragni","year":"2010","journal-title":"Cell Metab."},{"key":"ref_21","doi-asserted-by":"crossref","unstructured":"Park, S., Jang, J., Choi, M.D., Shin, Y.-A., Schutzler, S., Azhar, G., Ferrando, A.A., Wolfe, R.R., and Kim, I.-Y. (2020). The Anabolic Response to Dietary Protein Is Not Limited by the Maximal Stimulation of Protein Synthesis in Healthy Older Adults: A Randomized Crossover Trial. Nutrients, 12.","DOI":"10.3390\/nu12113276"},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"363","DOI":"10.1016\/j.gaitpost.2013.01.010","article-title":"The relationship between foot posture and lower limb kinematics during walking: A systematic review","volume":"38","author":"Buldt","year":"2013","journal-title":"Gait Posture"},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"519","DOI":"10.1016\/j.gaitpost.2010.07.013","article-title":"A comparison of foot kinematics in people with normal- and flat-arched feet using the Oxford Foot Model","volume":"32","author":"Levinger","year":"2010","journal-title":"Gait Posture"},{"key":"ref_24","doi-asserted-by":"crossref","unstructured":"Lin, K.W., Hu, C.J., Yang, W.W., Chou, L.W., Wei, S.H., Chen, C.S., and Sun, P.C. (2019). Biomechanical Evaluation and Strength Test of 3D-Printed Foot Orthoses. Appl. Bionics Biomech., 2019.","DOI":"10.1155\/2019\/4989534"},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"14","DOI":"10.2478\/pjst-2022-0003","article-title":"Comparison of Leg Muscle Activity During Level and Uphill Walking in Individuals with Flat Foot and Normal Foot: A Cross-Sectional Study","volume":"29","author":"Waheed","year":"2022","journal-title":"Polish J. Sport Tour."},{"key":"ref_26","doi-asserted-by":"crossref","unstructured":"Longo, G., Denaro, V., Ribeiro, A.P., Maria, S., and Jo\u00e3o, A. (2022). The Effect of Short and Long-Term Therapeutic Treatment with Insoles and Shoes on Pain, Function, and Plantar Load Parameters of Women with Plantar Fasciitis: A Randomized Controlled Trial. Medicina, 58.","DOI":"10.3390\/medicina58111546"},{"key":"ref_27","doi-asserted-by":"crossref","unstructured":"Ani\u015bko, B., Siatkowski, I., and W\u00f3jcik, M. (2024). Body mass composition analysis as a predictor of overweight and obesity in children and adolescents. Front. Public Health, 12.","DOI":"10.3389\/fpubh.2024.1371420"}],"container-title":["Medicina"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1648-9144\/61\/2\/281\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,9]],"date-time":"2025-10-09T16:28:09Z","timestamp":1760027289000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1648-9144\/61\/2\/281"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,2,6]]},"references-count":27,"journal-issue":{"issue":"2","published-online":{"date-parts":[[2025,2]]}},"alternative-id":["medicina61020281"],"URL":"https:\/\/doi.org\/10.3390\/medicina61020281","relation":{},"ISSN":["1648-9144"],"issn-type":[{"value":"1648-9144","type":"electronic"}],"subject":[],"published":{"date-parts":[[2025,2,6]]}}}