{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,11,5]],"date-time":"2026-11-05T01:28:48Z","timestamp":1793842128964,"version":"4.6.1"},"reference-count":31,"publisher":"Human Kinetics","issue":"1","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2022,1,1]]},"abstract":"\n \n Context<\/jats:bold>\n :\n <\/jats:italic>\n The importance of isometric trunk strength (ITS) among sport science professionals is higher than its actual reported effect size on either performance or low back pain (LBP) occurrence.\n \n Objective<\/jats:bold>\n :\n <\/jats:italic>\n To provide normative values of ITS and strength ratios, and to evaluate the effect of sex, sports discipline, and LBP status.\n \n Design<\/jats:bold>\n :\n <\/jats:italic>\n Crossover study.\n \n Setting<\/jats:bold>\n :\n <\/jats:italic>\n University research laboratory.\n \n Participants<\/jats:bold>\n :\n <\/jats:italic>\n Five hundred and sixty-seven elite athletes (186 females) with and without a history of LBP from different sports.\n \n Main Outcome Measure<\/jats:bold>\n :\n <\/jats:italic>\n Participants underwent ITS testing for trunk flexors, extensors, and lateral flexors. Normalized maximal strength (in newton meter per kilogram) and strength ratios were calculated. Differences between sex, LBP, and sport disciplines were assessed with 3-way analysis of variance (sex\u2009\u00d7\u2009LBP status\u2009\u00d7\u20097 sport categories) and partial eta-squared (\n \n ) effect size. The predictive validity of ITS for LBP was checked with receiver operating characteristics (area under the curve).\n \n Results<\/jats:bold>\n :\n <\/jats:italic>\n The authors found significant differences in extensor and flexor ITS in favor of male athletes (medium\n \n ,\n P<\/jats:italic>\n \u2009<\u2009.05), while sex differences in lateral flexion ITS had a low size effect (\n P<\/jats:italic>\n \u2009<\u2009.05). A low size effect was also observed for the differences in strength ratios extensors\/flexors (mean 1.47; 95% confidence interval, 1.45\u20131.50) and left flexors\/right flexors (mean 0.99; 95% confidence interval, 0.98\u20131.01) among sexes. The sport discipline-related differences generally had a low size effect. No significant differences in ITS were found between LBP and LBP-free athletes. Only 50% to 58% of athletes (area under the curve, 0.501\u20130.582) were correctly classified as LBP or LBP-free using different ITS and strength ratio variables.\n \n Conclusions<\/jats:bold>\n :\n <\/jats:italic>\n ITS and strength ratios have low predictive validity for LBP history but may discriminate between sex and sport disciplines. Our data are a useful reference point for meaningful individual results interpretation when athletes are evaluated during training or rehabilitation.\n <\/jats:p>","DOI":"10.1123\/jsr.2021-0002","type":"journal-article","created":{"date-parts":[[2021,9,22]],"date-time":"2021-09-22T11:15:33Z","timestamp":1632309333000},"page":"38-46","source":"Crossref","is-referenced-by-count":10,"title":["Isometric Trunk Strength Assessment of Athletes: Effects of Sex, Sport, and Low Back Pain History"],"prefix":"10.1123","volume":"31","author":[{"given":"Darjan","family":"Spudi\u0107","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Janez","family":"Vodi\u010dar","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Miha","family":"Vodi\u010dar","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Vedran","family":"Had\u017ei\u0107","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"100","reference":[{"issue":"3","key":"r1","series-title":"Sport Med","doi-asserted-by":"publisher","first-page":"401","DOI":"10.1007\/s40279-016-0597-7","article-title":"Core stability in athletes: a critical analysis of current guidelines","volume":"47","author":"Wirth K","year":"2017","unstructured":"Wirth K, Hartmann H, Mickel C, Szilvas E, Keiner M, Sander A. Core stability in athletes: a critical analysis of current guidelines. Sport Med. 2017;47(3):401\u2013414. doi:10.1007\/s40279-016-0597-710.1007\/s40279-016-0597-7"},{"issue":"3","key":"r2","series-title":"Sport Med","doi-asserted-by":"publisher","first-page":"401","DOI":"10.1007\/s40279-015-0426-4","article-title":"The role of trunk muscle strength for physical fitness and athletic performance in trained individuals: a systematic review and meta-analysis","volume":"46","author":"Prieske O","year":"2016","unstructured":"Prieske O, Muehlbauer T, Granacher U. The role of trunk muscle strength for physical fitness and athletic performance in trained individuals: a systematic review and meta-analysis. Sport Med. 2016;46(3):401\u2013419. doi:10.1007\/s40279-015-0426-410.1007\/s40279-015-0426-4"},{"key":"r3","series-title":"Low Back Disorders","author":"McGill S","year":"2007","unstructured":"McGill S. Low Back Disorders. 2nd ed. Champaign, IL: Human Kinetics; 2007."},{"issue":"6","key":"r4","series-title":"J Sport Health Sci","doi-asserted-by":"publisher","first-page":"692","DOI":"10.1016\/j.jshs.2016.08.011","article-title":"Isokinetic trunk flexion\u2013extension protocol to assess trunk muscle strength and endurance: reliability, learning effect, and sex differences","volume":"9","author":"Garc\u00eda-Vaquero MP","year":"2020","unstructured":"Garc\u00eda-Vaquero MP, Barbado D, Juan-Recio C, L\u00f3pez-Valenciano A, Vera-Garcia FJ. Isokinetic trunk flexion\u2013extension protocol to assess trunk muscle strength and endurance: reliability, learning effect, and sex differences. J Sport Health Sci. 2020;9(6):692\u2013701. doi:10.1016\/j.jshs.2016.08.01110.1016\/j.jshs.2016.08.01133308821"},{"issue":"2","key":"r5","series-title":"J Manipulative Physiol Ther","doi-asserted-by":"publisher","first-page":"110","DOI":"10.1067\/mmt.2001.112563","article-title":"Isometric back extension endurance tests: a review of the literature","volume":"24","author":"Moreau CE","year":"2001","unstructured":"Moreau CE, Green BN, Johnson CD, Susan R. Isometric back extension endurance tests: a review of the literature. J Manipulative Physiol Ther. 2001;24(2):110\u2013122. PubMed ID: 11208223 doi:10.1067\/mmt.2001.11256310.1067\/mmt.2001.11256311208223"},{"issue":"2","key":"r6","series-title":"J Spinal Disord","first-page":"114","article-title":"Body composition, endurance, strength, cross-sectional area, and density of MM erector spinae in men with and without low back pain","volume":"6","author":"Ultman G","year":"1993","unstructured":"Ultman G, Nordin M, Saraste H, Ohls\u00e8n H. Body composition, endurance, strength, cross-sectional area, and density of MM erector spinae in men with and without low back pain. J Spinal Disord. 1993;6(2):114\u2013123."},{"issue":"1","key":"r7","series-title":"Scand J Rehabil Med","first-page":"3","article-title":"Trunk muscle strength and back muscle endurance in construction workers with and without low back disorders","volume":"24","author":"Holmstr\u00f6m E","year":"1992","unstructured":"Holmstr\u00f6m E, Moritz U, Andersson M. Trunk muscle strength and back muscle endurance in construction workers with and without low back disorders. Scand J Rehabil Med. 1992;24(1):3\u201310. PubMed ID: 15349321534932"},{"issue":"6","key":"r8","series-title":"Clin Biomech","doi-asserted-by":"publisher","first-page":"323","DOI":"10.1016\/0268-0033(95)00002-3","article-title":"Static back endurance low-back pain and the risk of low-back pain","volume":"10","author":"Luoto S","year":"1995","unstructured":"Luoto S, Heliijvaara M, Hurri H, Alaranta H. Static back endurance low-back pain and the risk of low-back pain. Clin Biomech. 1995;10(6):323\u2013324. doi:10.1016\/0268-0033(95)00002-310.1016\/0268-0033(95)00002-3"},{"issue":"2","key":"r9","series-title":"Isokinet Exerc Sci","doi-asserted-by":"publisher","first-page":"99","DOI":"10.3233\/IES-2007-0256","article-title":"Reproducibility of trunk isokinetic strength findings in healthy individuals","volume":"15","author":"Dervi\u0161evi\u0107 E","year":"2007","unstructured":"Dervi\u0161evi\u0107 E, Had\u017ei\u0107 V, Burger H. Reproducibility of trunk isokinetic strength findings in healthy individuals. Isokinet Exerc Sci. 2007;15(2):99\u2013109. doi:10.3233\/IES-2007-025610.3233\/IES-2007-0256"},{"key":"r10","series-title":"Phys Ther Sport","doi-asserted-by":"publisher","first-page":"180","DOI":"10.1016\/j.ptsp.2018.10.005","article-title":"Reliability and validity of trunk flexor and trunk extensor strength measurements using handheld dynamometry in a healthy athletic population","volume":"34","author":"De Blaiser C","year":"2018","unstructured":"De Blaiser C, De Ridder R, Willems T, Danneels L, Roosen P. Reliability and validity of trunk flexor and trunk extensor strength measurements using handheld dynamometry in a healthy athletic population. Phys Ther Sport. 2018;34:180\u2013186. PubMed ID: 30366246 doi:10.1016\/j.ptsp.2018.10.00510.1016\/j.ptsp.2018.10.005"},{"issue":"12","key":"r11","series-title":"Arch Phys Med Rehabil","doi-asserted-by":"publisher","first-page":"1878","DOI":"10.1016\/j.apmr.2010.09.009","article-title":"Reliability of isometric strength measurements in trunk and neck region: patients with chronic neck pain compared with pain-free persons","volume":"91","author":"Scheuer R","year":"2010","unstructured":"Scheuer R, Friedrich M. Reliability of isometric strength measurements in trunk and neck region: patients with chronic neck pain compared with pain-free persons. Arch Phys Med Rehabil. 2010;91(12):1878\u20131883. PubMed ID: 21112429 doi:10.1016\/j.apmr.2010.09.00910.1016\/j.apmr.2010.09.00921112429"},{"issue":"2","key":"r12","series-title":"J Sport Sci Med","first-page":"365","article-title":"Assessment of Isometric trunk strength\u2014the relevance of body position and relationship between planes of movement","volume":"13","author":"Kocjan A","year":"2014","unstructured":"Kocjan A, Sarabon N. Assessment of Isometric trunk strength\u2014the relevance of body position and relationship between planes of movement. J Sport Sci Med. 2014;13(2):365\u2013370."},{"issue":"6","key":"r13","series-title":"Part H: J Eng Med.","first-page":"755","article-title":"Design and evaluation of a novel triaxial isometric trunk muscle strength measurement system. Proceedings of the Institution of Mechanical Engineers","volume":"223","author":"Azghani MR","year":"2009","unstructured":"Azghani MR, Farahmand F, Meghdari A, Vossoughi G, Parnianpour M. Design and evaluation of a novel triaxial isometric trunk muscle strength measurement system. Proceedings of the Institution of Mechanical Engineers. Part H: J Eng Med. 2009;223(6):755\u2013766. doi:10.1243\/09544119JEIM537"},{"issue":"3","key":"r14","series-title":"Int J Sports Phys Ther","first-page":"337","article-title":"The relationship between core endurance and back dysfunction in collegiate male athletes with and without nonspecific low back pain","volume":"11","author":"Abdelraouf OR","year":"2016","unstructured":"Abdelraouf OR. The relationship between core endurance and back dysfunction in collegiate male athletes with and without nonspecific low back pain. Int J Sports Phys Ther. 2016;11(3):337\u2013344. PubMed ID: 2727441927274419"},{"issue":"5","key":"r15","series-title":"TAF Prev Med Bull","first-page":"421","article-title":"Relations between back muscles endurance capacity and risk of low-back","volume":"9","author":"Chidozie E","year":"2010","unstructured":"Chidozie E, Olusola A. Relations between back muscles endurance capacity and risk of low-back. TAF Prev Med Bull. 2010;9(5):421\u2013426."},{"issue":"6","key":"r16","series-title":"Spine J","doi-asserted-by":"publisher","first-page":"673","DOI":"10.1016\/j.spinee.2006.03.012","article-title":"The association of low back pain, neuromuscular imbalance, and trunk extension strength in athletes","volume":"6","author":"Renkawitz T","year":"2006","unstructured":"Renkawitz T, Boluki D, Grifka J. The association of low back pain, neuromuscular imbalance, and trunk extension strength in athletes. Spine J. 2006;6(6):673\u2013683. PubMed ID: 17088198 doi:10.1016\/j.spinee.2006.03.01210.1016\/j.spinee.2006.03.01217088198"},{"issue":"7","key":"r17","series-title":"Phys Ther","doi-asserted-by":"publisher","first-page":"873","DOI":"10.2522\/ptj.20120457","article-title":"Multifidus and paraspinal muscle group cross-sectional areas of patients with low back pain and control patients: a systematic review with a focus on blinding","volume":"93","author":"Fortin M","year":"2013","unstructured":"Fortin M, Macedo LG. Multifidus and paraspinal muscle group cross-sectional areas of patients with low back pain and control patients: a systematic review with a focus on blinding. Phys Ther. 2013;93(7):873\u2013888. PubMed ID: 23504343 doi:10.2522\/ptj.2012045710.2522\/ptj.2012045723504343"},{"issue":"2","key":"r18","series-title":"Ann Rehabil Med","doi-asserted-by":"publisher","first-page":"234","DOI":"10.5535\/arm.2014.38.2.234","article-title":"Trunk muscles strength as a risk factor for nonspecific low back pain: a pilot study","volume":"38","author":"Cho KH","year":"2014","unstructured":"Cho KH, Beom JW, Lee TS, Lim JH, Lee TH, Yuk JH. Trunk muscles strength as a risk factor for nonspecific low back pain: a pilot study. Ann Rehabil Med. 2014;38(2):234\u2013240. PubMed ID: 24855618 doi:10.5535\/arm.2014.38.2.23410.5535\/arm.2014.38.2.23424855618"},{"key":"r19","series-title":"J Strength Cond Res","article-title":"The relationship between army physical fitness and functional capacities in infantry members of the slovenian armed forces","author":"\u0160imenko J","unstructured":"\u0160imenko J, Kov\u010dan B, Pori P, Vodi\u010dar J, Vodi\u010dar M, Had\u017ei\u0107 V. The relationship between army physical fitness and functional capacities in infantry members of the slovenian armed forces [published online ahead of print November 27, 2019]. J Strength Cond Res. doi:10.1519\/jsc.000000000000334431800475"},{"key":"r20","series-title":"Low Back Pain","first-page":"141","article-title":"Muscular performance assessment of trunk extensors: a critical appraisal of the literature","author":"Demoulin C","year":"2012","unstructured":"Demoulin C, Grosdent S, Smeets R, et\u00a0al. Muscular performance assessment of trunk extensors: a critical appraisal of the literature. In: Norasteh AA, ed. Low Back Pain. Rijeka, Croatia: InTech; 2012:141\u2013166. doi:10.5772\/34188"},{"issue":"4","key":"r21","series-title":"Eur J Appl Physiol","doi-asserted-by":"publisher","first-page":"322","DOI":"10.1007\/BF00571451","article-title":"Paradoxical variation of strength determinants with different rotation axes in trunk flexion and extension strength tests","volume":"68","author":"Rantanen P","year":"1994","unstructured":"Rantanen P, Airaksinen O, Penttinen E. Paradoxical variation of strength determinants with different rotation axes in trunk flexion and extension strength tests. Eur J Appl Physiol. 1994;68(4):322\u2013326. doi:10.1007\/BF0057145110.1007\/BF00571451"},{"issue":"70","key":"r22","series-title":"Healthcare","doi-asserted-by":"publisher","first-page":"1","DOI":"10.3390\/healthcare4030070","article-title":"Associations between trunk extension endurance and isolated lumbar extension strength in both asymptomatic participants and those with chronic low back pain","volume":"4","author":"Conway R","year":"2016","unstructured":"Conway R, Behennah J, Fisher J, Osborne N, Steele J. Associations between trunk extension endurance and isolated lumbar extension strength in both asymptomatic participants and those with chronic low back pain. Healthcare. 2016;4(70):1\u201311. doi:10.3390\/healthcare403007010.3390\/healthcare4030070"},{"issue":"1","key":"r23","series-title":"Sport Med","doi-asserted-by":"publisher","first-page":"1","DOI":"10.2165\/00007256-200030010-00001","article-title":"Measures of reliability in sports medicine and science","volume":"30","author":"Hopkins WG","year":"2000","unstructured":"Hopkins WG. Measures of reliability in sports medicine and science. Sport Med. 2000;30(1):1\u201315. doi:10.2165\/00007256-200030010-0000110.2165\/00007256-200030010-00001"},{"issue":"1","key":"r24","series-title":"Inf Technol Learn Perform J","first-page":"1","article-title":"The incorporation of effect size in information technology, learning, and performance research","volume":"21","author":"Kotrlik JW","year":"2003","unstructured":"Kotrlik JW, Williams HA. The incorporation of effect size in information technology, learning, and performance research. Inf Technol Learn Perform J. 2003;21(1):1\u20137."},{"issue":"2","key":"r25","series-title":"Int J Sports Physiol Perform","doi-asserted-by":"publisher","first-page":"131","DOI":"10.1123\/ijspp.3.2.131","article-title":"Reliability of measures obtained during single and repeated countermovement jumps","volume":"3","author":"Cormack SJ","year":"2008","unstructured":"Cormack SJ, Newton RU, McGulgan MR, Doyle TLA. Reliability of measures obtained during single and repeated countermovement jumps. Int J Sports Physiol Perform. 2008;3(2):131\u2013144. PubMed ID: 19208922 doi:10.1123\/ijspp.3.2.1311920892210.1123\/ijspp.3.2.131"},{"key":"r26","series-title":"Sport Biomech","article-title":"The effect of sex, age and sports specialisation on isometric trunk strength in Greek high level young athletes","author":"Tsolakis C","unstructured":"Tsolakis C, Simeonidis T, Georginis P, Cherouveim E, Methenitis S, Koulouvaris P. The effect of sex, age and sports specialisation on isometric trunk strength in Greek high level young athletes [published online ahead of print October 7, 2020]. Sport Biomech.\u00a0 doi:10.1080\/14763141.2020.1809699"},{"issue":"3","key":"r27","series-title":"J Orthop Sports Phys Ther","doi-asserted-by":"publisher","first-page":"165","DOI":"10.2519\/jospt.1980.1.3.165","article-title":"Muscle strength at the trunk*","volume":"1","author":"Smidt GL","year":"1980","unstructured":"Smidt GL, Amundsen LR, Dostal WF. Muscle strength at the trunk*. J Orthop Sports Phys Ther. 1980;1(3):165\u2013170. PubMed ID: 18810180 doi:10.2519\/jospt.1980.1.3.16510.2519\/jospt.1980.1.3.165"},{"key":"r28","series-title":"Muscle Strength","doi-asserted-by":"publisher","DOI":"10.1201\/9780203503591","author":"Kumar S","year":"2004","unstructured":"Kumar S. Muscle Strength. Boca Raton, FL: CRC Press; 2004.10.1201\/9780203503591"},{"issue":"3","key":"r29","series-title":"Arch Phys Med Rehabil","doi-asserted-by":"publisher","first-page":"513","DOI":"10.1016\/j.apmr.2007.08.160","article-title":"Effect of isometric upper-extremity exercises on the activation of core stabilizing muscles","volume":"89","author":"Tarnanen SP","year":"2008","unstructured":"Tarnanen SP, Ylinen JJ, Siekkinen KM, M\u00e4lki\u00e4 EA, Kautiainen HJ, H\u00e4kkinen AH. Effect of isometric upper-extremity exercises on the activation of core stabilizing muscles. Arch Phys Med Rehabil. 2008;89(3):513\u2013521. PubMed ID: 18295631 doi:10.1016\/j.apmr.2007.08.16010.1016\/j.apmr.2007.08.16018295631"},{"issue":"7","key":"r30","series-title":"Am Fam Physician","first-page":"421","article-title":"Mechanical low back pain","volume":"98","author":"Will JS","year":"2018","unstructured":"Will JS, Bury DC, Miller JA. Mechanical low back pain. Am Fam Physician. 2018;98(7):421\u2013428. PubMed ID: 3025242530252425"},{"issue":"9","key":"r31","series-title":"J Thorac Oncol","doi-asserted-by":"publisher","first-page":"1315","DOI":"10.1097\/JTO.0b013e3181ec173d","article-title":"Receiver operating characteristic curve in diagnostic test assessment","volume":"5","author":"Mandrekar JN","year":"2010","unstructured":"Mandrekar JN. Receiver operating characteristic curve in diagnostic test assessment. J Thorac Oncol. 2010;5(9):1315\u20131316. PubMed ID: 20736804 doi:10.1097\/JTO.0b013e3181ec173d10.1097\/JTO.0b013e3181ec173d20736804"}],"container-title":["Journal of Sport Rehabilitation"],"original-title":[],"link":[{"URL":"https:\/\/journals.humankinetics.com\/view\/journals\/jsr\/31\/1\/article-p38.xml","content-type":"text\/html","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/journals.humankinetics.com\/downloadpdf\/journals\/jsr\/31\/1\/article-p38.xml","content-type":"text\/html","content-version":"vor","intended-application":"syndication"},{"URL":"https:\/\/journals.humankinetics.com\/downloadpdf\/journals\/jsr\/31\/1\/article-p38.xml","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,11,5]],"date-time":"2026-11-05T01:14:59Z","timestamp":1793841299000},"score":1,"resource":{"primary":{"URL":"https:\/\/journals.humankinetics.com\/view\/journals\/jsr\/31\/1\/article-p38.xml"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2022,1,1]]},"references-count":31,"journal-issue":{"issue":"1"},"URL":"https:\/\/doi.org\/10.1123\/jsr.2021-0002","relation":{},"ISSN":["1056-6716","1543-3072"],"issn-type":[{"value":"1056-6716","type":"print"},{"value":"1543-3072","type":"electronic"}],"subject":[],"published":{"date-parts":[[2022,1,1]]}}}