{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,14]],"date-time":"2026-03-14T03:09:30Z","timestamp":1773457770846,"version":"3.50.1"},"reference-count":19,"publisher":"Wiley","issue":"1","license":[{"start":{"date-parts":[[2004,10,13]],"date-time":"2004-10-13T00:00:00Z","timestamp":1097625600000},"content-version":"vor","delay-in-days":6495,"URL":"http:\/\/onlinelibrary.wiley.com\/termsAndConditions#vor"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Muscle and Nerve"],"published-print":{"date-parts":[[1987,1]]},"abstract":"<jats:title>Abstract<\/jats:title><jats:p>The present study assessed creatine kinase (CK) activity, CK MM isoforms, and muscle soreness following an exercise regimen designed to induce skeletal muscle damage. Eight college\u2010age subjects performed 40 maximal isometric contractions of the knee extensor muscles (10\u2010second contraction\/20\u2010second rest). Serum samples and soreness ratings were taken prior to and 2, 6, 18, and 24 hours after the exercise. The CK MM1 and CK MM3 isoforms were determined by flatbed isoelectric focusing (IEF). In serum, the MM1 isoform (the pure gene product) is considered to be evidence of newly released CK from muscle, as upon entering the plasma, the CK MM1 is converted to MM2 and then MM3. A significant increase in serum CK activity was found at 6 hours and remained elevated at 24 hours. CK MM1 increased significantly at 2 hours, peaked at 6 hours, then approached baseline. Soreness did not increase significantly until 18 hours. Analysis of CK isoforms in serum can provide an earlier indicator of skeletal muscle damage than total CK or perception of soreness and may be useful in tracking the time course of skeletal muscle damage and repair.<\/jats:p>","DOI":"10.1002\/mus.880100108","type":"journal-article","created":{"date-parts":[[2005,1,1]],"date-time":"2005-01-01T07:17:59Z","timestamp":1104563879000},"page":"41-44","source":"Crossref","is-referenced-by-count":24,"title":["Creatine kinase isoforms following isometric exercise"],"prefix":"10.1002","volume":"10","author":[{"given":"Priscilla M.","family":"Clarkson","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Fred S.","family":"Apple","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"William C.","family":"Byrnes","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kathleen M.","family":"McCormick","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Philip","family":"Triffletti","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"311","published-online":{"date-parts":[[2004,10,13]]},"reference":[{"key":"e_1_2_1_2_2","doi-asserted-by":"crossref","first-page":"402","DOI":"10.1093\/clinchem\/31.3.402","article-title":"MM subisoenzymes of creatine kinase as an index of disease activity in polymyositis","volume":"31","author":"Annesley TM","year":"1985","journal-title":"Clin Chem"},{"key":"e_1_2_1_3_2","doi-asserted-by":"publisher","DOI":"10.1249\/00005768-198412000-00002"},{"issue":"3","key":"e_1_2_1_4_2","doi-asserted-by":"crossref","first-page":"710","DOI":"10.1152\/jappl.1985.59.3.710","article-title":"Delayed onset muscle soreness following repeated bouts of downhill running","volume":"59","author":"Byrnes WC","year":"1985","journal-title":"J Appl Physiol"},{"key":"e_1_2_1_5_2","doi-asserted-by":"publisher","DOI":"10.1055\/s-2008-1026078"},{"key":"e_1_2_1_6_2","doi-asserted-by":"publisher","DOI":"10.1007\/BF00422856"},{"key":"e_1_2_1_7_2","doi-asserted-by":"publisher","DOI":"10.1161\/01.CIR.71.2.363"},{"key":"e_1_2_1_8_2","doi-asserted-by":"publisher","DOI":"10.1007\/BF00421520"},{"key":"e_1_2_1_9_2","doi-asserted-by":"publisher","DOI":"10.1080\/02701367.1984.10608400"},{"key":"e_1_2_1_10_2","doi-asserted-by":"publisher","DOI":"10.1161\/01.CIR.67.6.1283"},{"key":"e_1_2_1_11_2","doi-asserted-by":"publisher","DOI":"10.1002\/mus.880060507"},{"key":"e_1_2_1_12_2","doi-asserted-by":"publisher","DOI":"10.1016\/0022-510X(83)90058-8"},{"key":"e_1_2_1_13_2","doi-asserted-by":"crossref","first-page":"662","DOI":"10.1093\/clinchem\/30.5.662","article-title":"Carboxypeptidase\u2010catalyzed hydrolysis of C\u2010terminal lysine: mechanism for in vivo production of multiple forms of creatine kinase in plasma","volume":"30","author":"Perryman MB","year":"1984","journal-title":"Clin Chem"},{"key":"e_1_2_1_14_2","doi-asserted-by":"publisher","DOI":"10.1007\/BF01946672"},{"key":"e_1_2_1_15_2","first-page":"696","article-title":"An improved procedure for serum creatine phosphokinase determination","volume":"69","author":"Rosalki SB","year":"1967","journal-title":"J Lab Clin Med"},{"key":"e_1_2_1_16_2","doi-asserted-by":"publisher","DOI":"10.1249\/00005768-198315010-00010"},{"key":"e_1_2_1_17_2","doi-asserted-by":"publisher","DOI":"10.1249\/00005768-198315060-00004"},{"key":"e_1_2_1_18_2","doi-asserted-by":"publisher","DOI":"10.1016\/0002-8703(83)90356-3"},{"key":"e_1_2_1_19_2","first-page":"866","article-title":"Postsynthetic modifications in the creatine kinase M\u2010chain and the disappearance of the enzyme from the circulation. The role and function of a new serum protein?","volume":"24","author":"Wevers R","year":"1983","journal-title":"J Clin Chem Clin Biochem"},{"key":"e_1_2_1_20_2","first-page":"109","article-title":"Postsynthetic variants of creatine kinase MM","volume":"98","author":"Yasmineh WG","year":"1981","journal-title":"J Lab Clin Med"}],"container-title":["Muscle &amp; Nerve"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/api.wiley.com\/onlinelibrary\/tdm\/v1\/articles\/10.1002%2Fmus.880100108","content-type":"unspecified","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/pdf\/10.1002\/mus.880100108","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2023,10,21]],"date-time":"2023-10-21T03:01:47Z","timestamp":1697857307000},"score":1,"resource":{"primary":{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/10.1002\/mus.880100108"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[1987,1]]},"references-count":19,"journal-issue":{"issue":"1","published-print":{"date-parts":[[1987,1]]}},"alternative-id":["10.1002\/mus.880100108"],"URL":"https:\/\/doi.org\/10.1002\/mus.880100108","archive":["Portico"],"relation":{},"ISSN":["0148-639X","1097-4598"],"issn-type":[{"value":"0148-639X","type":"print"},{"value":"1097-4598","type":"electronic"}],"subject":[],"published":{"date-parts":[[1987,1]]}}}