{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,11,2]],"date-time":"2026-11-02T19:53:31Z","timestamp":1793649211963,"version":"4.5.1"},"reference-count":20,"publisher":"National Athletic Trainers' Association","issue":"5","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2008,9]]},"abstract":"<jats:title>Abstract<\/jats:title>\n        <jats:sec>\n          <jats:title>Context:<\/jats:title>\n          <jats:p>Single-limb squats on a decline angle have been suggested as a rehabilitative intervention to target the knee extensors. Investigators, however, have presented very little empirical research in which they have documented the biomechanics of these exercises or have determined the optimum angle of decline used.<\/jats:p>\n        <\/jats:sec>\n        <jats:sec>\n          <jats:title>Objective:<\/jats:title>\n          <jats:p>To determine the involvement of the gastrocnemius and rectus femoris muscles and the external ankle and knee joint moments at 60\u00b0 of knee flexion while performing a single-limb squat at different decline angles.<\/jats:p>\n        <\/jats:sec>\n        <jats:sec>\n          <jats:title>Design:<\/jats:title>\n          <jats:p>Participants acted as their own controls in a repeated-measures design.<\/jats:p>\n        <\/jats:sec>\n        <jats:sec>\n          <jats:title>Patients or Other Participants:<\/jats:title>\n          <jats:p>We recruited 10 participants who had no pain, injury, or neurologic disorder.<\/jats:p>\n        <\/jats:sec>\n        <jats:sec>\n          <jats:title>Intervention(s):<\/jats:title>\n          <jats:p> Participants performed single-limb squats at different decline angles.<\/jats:p>\n        <\/jats:sec>\n        <jats:sec>\n          <jats:title>Main Outcome Measure(s):<\/jats:title>\n          <jats:p>Angle-specific knee and ankle moments were calculated at 60\u00b0 of knee flexion. Angle-specific electromyography (EMG) activity was calculated at 60\u00b0 of knee flexion. Integrated EMG also was calculated to determine the level of muscle activity over the entire squat.<\/jats:p>\n        <\/jats:sec>\n        <jats:sec>\n          <jats:title>Results:<\/jats:title>\n          <jats:p>An increase was seen in the knee moments (<jats:italic>P<\/jats:italic> &lt; .05) and integrated EMG in the rectus femoris (<jats:italic>P<\/jats:italic> &lt; .001) as the decline angle increased. A decrease was seen in the ankle moments as the decline angle increased (<jats:italic>P<\/jats:italic> \u200a=\u200a .001), but EMG activity in the gastrocnemius increased between 16\u00b0 and 24\u00b0 (<jats:italic>P<\/jats:italic> \u200a=\u200a .018).<\/jats:p>\n        <\/jats:sec>\n        <jats:sec>\n          <jats:title>Conclusions:<\/jats:title>\n          <jats:p>As the decline angle increased, the knee extensor moment and EMG activity increased. As the decline angle increased, the ankle plantar-flexor moments decreased; however, an increase in the EMG activity was seen with the 24\u00b0 decline angle compared with the 16\u00b0 decline angle. This indicates that decline squats at an angle greater than 16\u00b0 may not reduce passive calf tension, as was suggested previously, and may provide no mechanical advantage for the knee.<\/jats:p>\n        <\/jats:sec>","DOI":"10.4085\/1062-6050-43.5.477","type":"journal-article","created":{"date-parts":[[2009,12,30]],"date-time":"2009-12-30T15:36:57Z","timestamp":1262187417000},"page":"477-482","source":"Crossref","is-referenced-by-count":31,"title":["A Biomechanical Investigation of A Single-Limb Squat: Implications for Lower Extremity Rehabilitation Exercise"],"prefix":"10.4085","volume":"43","author":[{"given":"Jim","family":"Richards","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dominic","family":"Thewlis","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"James","family":"Selfe","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Andrew","family":"Cunningham","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Colin","family":"Hayes","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"2557","reference":[{"issue":"5","key":"i1062-6050-43-5-477-Roos1","series-title":"Scand J Med Sci Sports","first-page":"286","article-title":"Clinical improvement after 6 weeks of eccentric exercise in patients with mid-portion Achilles tendinopathy: a randomized trial with 1-year follow up.","volume":"14","author":"Roos, E.","year":"2004","unstructured":"Roos, E., M.Engstrom, A.Lagerquist, and B.Soderberg. Clinical improvement after 6 weeks of eccentric exercise in patients with mid-portion Achilles tendinopathy: a randomized trial with 1-year follow up.Scand J Med Sci Sports2004. 14 (5):286\u2013295."},{"issue":"5","key":"i1062-6050-43-5-477-Cook1","series-title":"Br J Sports Med","first-page":"291","article-title":"What is the most appropriate treatment for patellar tendinopathy?","volume":"35","author":"Cook, J.","year":"2001","unstructured":"Cook, J. and K.Khan. What is the most appropriate treatment for patellar tendinopathy?Br J Sports Med2001. 35 (5):291\u2013294."},{"issue":"1","key":"i1062-6050-43-5-477-Ohberg1","series-title":"Br J Sports Med","first-page":"8","article-title":"Eccentric training in patients with chronic Achilles tendinosis: normalised tendon structure and decreased thickness at follow up.","volume":"38","author":"Ohberg, L.","year":"2002","unstructured":"Ohberg, L., R.Lorentzon, and H.Alfredson. Eccentric training in patients with chronic Achilles tendinosis: normalised tendon structure and decreased thickness at follow up.Br J Sports Med2002. 38 (1):8\u201311."},{"issue":"3","key":"i1062-6050-43-5-477-Panni1","series-title":"Am J Sports Med","first-page":"392","article-title":"Patellar tendinopathy in athletes: outcome of nonoperative and operative management.","volume":"28","author":"Panni, A. S.","year":"2000","unstructured":"Panni, A. S., M.Tartarone, and N.Maffulli. Patellar tendinopathy in athletes: outcome of nonoperative and operative management.Am J Sports Med2000. 28 (3):392\u2013397."},{"issue":"1","key":"i1062-6050-43-5-477-Cannell1","series-title":"Br J Sports Med","first-page":"60","article-title":"A randomised clinical trial of the efficacy of drop squats or leg extension\/leg curl exercises to treat clinically diagnosed jumper's knee in athletes: a pilot study.","volume":"35","author":"Cannell, L. J.","year":"2001","unstructured":"Cannell, L. J., J. 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Superior results with eccentric compared to concentric quadriceps training in patients with jumper's knee: a prospective randomised study.Br J Sports Med2005. 39 (11):847\u2013850."},{"issue":"2","key":"i1062-6050-43-5-477-Young1","series-title":"Br J Sports Med","first-page":"102","article-title":"Eccentric decline squat protocol offers superior results at 12 months compared with traditional eccentric protocol for patellar tendinopathy in volleyball players.","volume":"39","author":"Young, M. A.","year":"2005","unstructured":"Young, M. A., J. L.Cook, C. R.Purdam, Z. S.Kiss, and H.Alfredson. Eccentric decline squat protocol offers superior results at 12 months compared with traditional eccentric protocol for patellar tendinopathy in volleyball players.Br J Sports Med2005. 39 (2):102\u2013105."},{"issue":"4","key":"i1062-6050-43-5-477-Zwerver1","series-title":"Br J Sports Med","first-page":"264","article-title":"Biomechanical analysis of the single-leg decline squat.","volume":"41","author":"Zwerver, J.","year":"2007","unstructured":"Zwerver, J., S. W.Bredeweg, and A. L.Hof. Biomechanical analysis of the single-leg decline squat.Br J Sports Med2007. 41 (4):264\u2013268."},{"issue":"6","key":"i1062-6050-43-5-477-Frohm1","series-title":"Clin Biomech (Bristol, Avon)","first-page":"704","article-title":"Patellar tendon load in different types of eccentric squats.","volume":"22","author":"Frohm, A.","year":"2007","unstructured":"Frohm, A., K.Halvorsen, and A.Thorstensson. 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The effects of normalization method on antagonistic activity patterns during eccentric and concentric isokinetic knee extension and flexion.J Electromyogr Kinesiol1996. 6 (4):235\u2013245."}],"container-title":["Journal of Athletic Training"],"original-title":[],"link":[{"URL":"https:\/\/nata.kglmeridian.com\/view\/journals\/attr\/43\/5\/article-p477.xml","content-type":"text\/html","content-version":"vor","intended-application":"text-mining"},{"URL":"http:\/\/meridian.allenpress.com\/jat\/article-pdf\/43\/5\/477\/1453385\/1062-6050-43_5_477.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"syndication"},{"URL":"https:\/\/nata.kglmeridian.com\/downloadpdf\/journals\/attr\/43\/5\/article-p477.xml","content-type":"text\/html","content-version":"vor","intended-application":"syndication"},{"URL":"https:\/\/nata.kglmeridian.com\/downloadpdf\/journals\/attr\/43\/5\/article-p477.xml","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,6,12]],"date-time":"2025-06-12T00:36:28Z","timestamp":1749688588000},"score":1,"resource":{"primary":{"URL":"https:\/\/nata.kglmeridian.com\/view\/journals\/attr\/43\/5\/article-p477.xml"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2008,9]]},"references-count":20,"journal-issue":{"issue":"5"},"URL":"https:\/\/doi.org\/10.4085\/1062-6050-43.5.477","relation":{},"ISSN":["1062-6050"],"issn-type":[{"value":"1062-6050","type":"print"}],"subject":[],"published":{"date-parts":[[2008,9]]}}}