{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,17]],"date-time":"2026-04-17T07:56:11Z","timestamp":1776412571196,"version":"3.51.2"},"reference-count":0,"publisher":"Portland Press Ltd.","issue":"1","content-domain":{"domain":["portlandpress.com"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[1995,1,1]]},"abstract":"<jats:p>1. Growth hormone-deficient hypopituitary adults often complain of weakness and fatigue. The cause of the fatigue is unknown but could be an increased proportion of fast, fatiguable, type 2 fibres in the muscle. The aim of this study was to examine the contractile properties of the quadriceps muscle in a group of these patients compared with healthy controls. Changes in these properties were also examined in a small subset of the patients following growth hormone replacement.<\/jats:p>\n               <jats:p>2. Isometric strength, half-relaxation time from a twitch (t1\/2) and the force\u2014frequency relationship were measured using electrically evoked contractions in 14 growth hormone-deficient patients and 14 age- and sex-matched controls. Six patients were restudied following 6\u201324 month's replacement therapy with growth hormone (daily dose 0.04 \u00b1 0.01 i.u.\/kg).<\/jats:p>\n               <jats:p>3. The growth hormone-deficient patients had a significantly lower t1\/2 than the controls (46.1 \u00b1 6.1 ms versus 56.1 \u00b1 10.5 ms respectively; P = 0.0072; mean \u00b1 SD). The 10\/100% ratio was also significantly lower in growth-hormone-deficient patients (38.6 \u00b1 9.9% versus 52.3 \u00b1 8.0%; P = 0.0005), as was muscle strength (349 \u00b1 99 N versus 493 \u00b1 215 N; P = 0.036). Following growth hormone replacement, muscle strength increased significantly (P &amp;lt; 0.05). The 10\/100% ratio also increased towards control values, but this change was not significant.<\/jats:p>\n               <jats:p>4. These results demonstrate that the relaxation times of the quadriceps are significantly shorter and that the force\u2014frequency relationship shifted to the right in growth hormone-deficient patients, which is consistent with a greater proportion of type 2 fibres within the muscle. Preliminary data on a small group suggest that replacement with growth hormone results in a change in these properties towards that of controls.<\/jats:p>","DOI":"10.1042\/cs0880067","type":"journal-article","created":{"date-parts":[[2015,8,7]],"date-time":"2015-08-07T11:37:12Z","timestamp":1438947432000},"page":"67-71","update-policy":"https:\/\/doi.org\/10.1042\/crossmark_policy","source":"Crossref","is-referenced-by-count":39,"title":["Contractile Properties of the Quadriceps Muscle in Growth Hormone-Deficient Hypopituitary Adults"],"prefix":"10.1042","volume":"88","author":[{"given":"Olga M.","family":"Rutherford","sequence":"first","affiliation":[{"name":"Department of Physiology, London, U.K."}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Salem A.","family":"Beshyah","sequence":"additional","affiliation":[{"name":"Unit of Metabolic Medicine, St. Mary's Hospital Medical School, London, U.K."}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jonathan","family":"Schott","sequence":"additional","affiliation":[{"name":"Department of Physiology, London, U.K."}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yvonne","family":"Watkins","sequence":"additional","affiliation":[{"name":"Department of Physiology, London, U.K."}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Desmond G.","family":"Johnston","sequence":"additional","affiliation":[{"name":"Unit of Metabolic Medicine, St. Mary's Hospital Medical School, London, U.K."}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"288","container-title":["Clinical Science"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/portlandpress.com\/clinsci\/article-pdf\/88\/1\/67\/465572\/cs0880067.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"syndication"},{"URL":"https:\/\/portlandpress.com\/clinsci\/article-pdf\/88\/1\/67\/465572\/cs0880067.pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2021,12,1]],"date-time":"2021-12-01T22:50:49Z","timestamp":1638399049000},"score":1,"resource":{"primary":{"URL":"https:\/\/portlandpress.com\/clinsci\/article\/88\/1\/67\/76338\/Contractile-Properties-of-the-Quadriceps-Muscle-in"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[1995,1,1]]},"references-count":0,"journal-issue":{"issue":"1","published-print":{"date-parts":[[1995,1,1]]}},"URL":"https:\/\/doi.org\/10.1042\/cs0880067","relation":{},"ISSN":["0143-5221","1470-8736"],"issn-type":[{"value":"0143-5221","type":"print"},{"value":"1470-8736","type":"electronic"}],"subject":[],"published":{"date-parts":[[1995,1,1]]}}}