{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,22]],"date-time":"2026-06-22T10:53:40Z","timestamp":1782125620145,"version":"3.54.5"},"reference-count":29,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2026,6,22]],"date-time":"2026-06-22T00:00:00Z","timestamp":1782086400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Life"],"abstract":"<jats:p>Background: This study aimed to compare the effects of unstable strength training (UST) and traditional strength training (TST) on lower-body stability in adolescent volleyball players in China. Methods: This stratified randomized controlled trial recruited 62 eligible athletes from Shandong Province. Participants were assigned to either the UST group or the TST group, and both groups completed a 10-week training program. Results: Multivariate analysis of variance (MANOVA) for within-group effects revealed statistically significant improvements in all dependent variables for both the UST and TST groups (p &lt; 0.05), FMS [F = 35.112, p &lt; 0.001, \u03b72 = 0.377]; and balance ability differences, left-side score (LS) [F = 8.268, p &lt; 0.001, \u03b72 = 0.125], right-side score (RS) [F = 8.094, p &lt; 0.001, \u03b72 = 0.122]. Furthermore, after controlling for covariates, MANCOVA analysis for between-group effects still showed statistically significant differences between the UST and TST groups on all post-test dependent variables. These differences included: functional differences, FMS [F = 34.412, p &lt; 0.001, \u03b72 = 0.389]; LS [F = 8.079, p &lt; 0.01, \u03b72 = 0.130]; and RS [F = 8.532, p &lt; 0.001, \u03b72 = 0.136]. Conclusion: UST is more effective than TST in improving athletes\u2019 lower-body stability performance. Future studies should explore the application of UST in other sports and examine its effects on parameters beyond functional movement and balance.<\/jats:p>","DOI":"10.3390\/life16061036","type":"journal-article","created":{"date-parts":[[2026,6,22]],"date-time":"2026-06-22T09:49:55Z","timestamp":1782121795000},"page":"1036","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["The Effects of Unstable Strength Training on Lower Limb Stability in Adolescent Volleyball Players in China"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0009-0005-5753-5713","authenticated-orcid":false,"given":"Kaiyuan","family":"Dong","sequence":"first","affiliation":[{"name":"Department of Sports Studies, Faculty of Educational Studies, Universiti Putra Malaysia, Serdang 43400, Malaysia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Borhannudin Bin","family":"Abdullah","sequence":"additional","affiliation":[{"name":"Department of Sports Studies, Faculty of Educational Studies, Universiti Putra Malaysia, Serdang 43400, Malaysia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,6,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"421","DOI":"10.1007\/s40279-015-0428-2","article-title":"Agility in team sports: Testing, training and factors affecting performance","volume":"46","author":"Paul","year":"2016","journal-title":"Sports Med."},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Garcia, S., Delattre, N., Berton, E., Divrechy, G., and Rao, G. (2022). Comparison of landing kinematics and kinetics between experienced and novice volleyball players during block and spike jumps. BMC Sports Sci. Med. Rehabil., 14.","DOI":"10.1186\/s13102-022-00496-0"},{"key":"ref_3","first-page":"1357","article-title":"The effects of high-intensity functional training on aerobic capacity, metabolic adaptation and neuromuscular responses in young female volleyball players","volume":"9","year":"2021","journal-title":"Eur. J. Mol. Clin. Med."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"4979","DOI":"10.1038\/s41598-026-35725-w","article-title":"Functional movement screen and asymmetries in female volleyball players across playing positions","volume":"16","author":"Uysal","year":"2026","journal-title":"Sci. Rep."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"500","DOI":"10.1177\/1941738113477815","article-title":"Instability resistance training across the exercise continuum","volume":"5","author":"Behm","year":"2013","journal-title":"Sports Health"},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"1645","DOI":"10.1007\/s40279-015-0384-x","article-title":"Effects of strength training using unstable surfaces on strength, power and balance performance across the lifespan: A systematic review and meta-analysis","volume":"45","author":"Behm","year":"2015","journal-title":"Sports Med."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"e20212","DOI":"10.7717\/peerj.20212","article-title":"Instability core training vs traditional core training on trunk strength and sprint performance among athletes: A systematic review and meta-analysis","volume":"13","author":"Gao","year":"2025","journal-title":"PeerJ"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"245","DOI":"10.1016\/j.jtcme.2016.05.007","article-title":"Instability resistance training for health and performance","volume":"7","year":"2017","journal-title":"J. Tradit. Complement. Med."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"398","DOI":"10.54141\/psbd.1361176","article-title":"Muscle Activation during Squat on Different Surfaces","volume":"14","year":"2023","journal-title":"Pamukkale J. Sport Sci."},{"key":"ref_10","doi-asserted-by":"crossref","unstructured":"Zemkov\u00e1, E., and Zapletalov\u00e1, L. (2022). The role of neuromuscular control of postural and core stability in functional movement and athlete performance. Front. Physiol., 13.","DOI":"10.3389\/fphys.2022.796097"},{"key":"ref_11","first-page":"391","article-title":"Effect of instability resistance training on core muscle strength among athletes: A systematic review","volume":"12","author":"Abdullah","year":"2024","journal-title":"Int. J. Hum. Mov. Sports Sci."},{"key":"ref_12","first-page":"245","article-title":"Effects of core stability training on balance and performance","volume":"21","author":"Zarei","year":"2022","journal-title":"J. Sports Sci. Med."},{"key":"ref_13","doi-asserted-by":"crossref","unstructured":"Chomiuk, T., Kasiak, P., Filipek, A., Mamcarz, A., and \u015ali\u017c, D. (2025). Functional Movement Screen scores are comparable in volleyball players with and without back pain\u2014The FMS-VBP study. J. Clin. Med., 14.","DOI":"10.3390\/jcm14186502"},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"65","DOI":"10.1123\/jsr.2018-0015","article-title":"Landing kinematics, sports performance, and isokinetic strength in adolescent male volleyball athletes: Influence of core training","volume":"29","author":"Tsai","year":"2020","journal-title":"J. Sport Rehabil."},{"key":"ref_15","first-page":"12","article-title":"Effects of 6 weeks core training on balance, strength and service performance in volleyball players","volume":"5","year":"2019","journal-title":"Eur. J. Phys. Educ. Sport Sci."},{"key":"ref_16","doi-asserted-by":"crossref","unstructured":"Yu, T., Xu, Y., Zhang, Z., Sun, Y., Zhong, J., and Ding, C. (2025). The impact of core training on overall athletic performance in different sports: A comprehensive meta-analysis. BMC Sports Sci. Med. Rehabil., 17.","DOI":"10.1186\/s13102-025-01159-6"},{"key":"ref_17","doi-asserted-by":"crossref","unstructured":"Erol, M., G\u00f6zl\u00fckaya Girginer, F., Seyhan, S., Acar, G., Cerit, G., Uzun, M., and Soylu, C. (2025). Predicting injury risk in young female volleyball players through movement and jump assessments. Front. Public Health, 13.","DOI":"10.3389\/fpubh.2025.1658046"},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"228","DOI":"10.5455\/jcmr.2023.14.02.35","article-title":"Anthropometric and jumping profiles of U19 boys\u2019 volleyball players in the World Championship 2019","volume":"14","author":"Younis","year":"2023","journal-title":"J. Complement. Med. Res."},{"key":"ref_19","first-page":"e678","article-title":"Relationships between functional movement quality and sports performance in elite figure skating athletes of China","volume":"38","author":"Zhitao","year":"2024","journal-title":"J. Strength Cond. Res."},{"key":"ref_20","unstructured":"Chipman, J.J., Mayberry, L., and Greevy, R.A. (2022). REMATCHING ON-THE-FLY: Sequential matched randomization and a case for covariate-adaptive randomization. arXiv, Available online: https:\/\/arxiv.org\/abs\/2203.13797."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"135","DOI":"10.2478\/hukin-2019-0062","article-title":"Similar muscular adaptations in resistance training performed two versus three days per week","volume":"68","author":"Lasevicius","year":"2019","journal-title":"J. Hum. Kinet."},{"key":"ref_22","doi-asserted-by":"crossref","unstructured":"Matuszczyk, F., Trybulski, R., Ga\u0142\u0119ziok, K., Olaniszyn, G., Terbalyan, A., and Wilk, M. (2025). Effect of 10-week plyometric training on anaerobic performance and biomechanical properties of the muscles in football players: Randomized controlled trial. Appl. Sci., 15.","DOI":"10.3390\/app15031451"},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"504","DOI":"10.1542\/peds.94.4.504","article-title":"Predicting adult stature without using skeletal age: The Khamis-Roche method","volume":"94","author":"Khamis","year":"1994","journal-title":"Pediatrics"},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"95","DOI":"10.1097\/MLR.0000000000001664","article-title":"Guidelines for designing and evaluating feasibility pilot studies","volume":"60","author":"Teresi","year":"2022","journal-title":"Med. Care"},{"key":"ref_25","doi-asserted-by":"crossref","unstructured":"Bertozzi, F., Brunetti, C., Maver, P., Galli, M., and Tarabini, M. (2025). The role of age and maturation on jump performance and postural control in female adolescent volleyball players over a season. BMC Sports Sci. Med. Rehabil., 17.","DOI":"10.1186\/s13102-025-01134-1"},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"1931","DOI":"10.1519\/JSC.0b013e3181df7fe4","article-title":"Training adaptations associated with an 8-week instability resistance training program with recreationally active individuals","volume":"24","author":"Sparkes","year":"2010","journal-title":"J. Strength Cond. Res."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"400","DOI":"10.1123\/ijspp.2.4.400","article-title":"Effect of instability and resistance on unintentional squat-lifting kinetics","volume":"2","author":"Drinkwater","year":"2007","journal-title":"Int. J. Sports Physiol. Perform."},{"key":"ref_28","first-page":"525","article-title":"The Effect of Core Training on Agility, Explosive Strength and Balance in Young Female Volleyball Players","volume":"7","author":"Ergin","year":"2022","journal-title":"J. Sport Sci. Res."},{"key":"ref_29","first-page":"389","article-title":"Functional movement and injury prevention","volume":"49","author":"Pfeifer","year":"2019","journal-title":"Sports Med."}],"container-title":["Life"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2075-1729\/16\/6\/1036\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,6,22]],"date-time":"2026-06-22T10:36:29Z","timestamp":1782124589000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2075-1729\/16\/6\/1036"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,6,22]]},"references-count":29,"journal-issue":{"issue":"6","published-online":{"date-parts":[[2026,6]]}},"alternative-id":["life16061036"],"URL":"https:\/\/doi.org\/10.3390\/life16061036","relation":{},"ISSN":["2075-1729"],"issn-type":[{"value":"2075-1729","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,6,22]]}}}