Ratio of Creatine Kinase 2 Mass Concentration to Total Creatine Kinase Activity not Altered by Heavy Physical Exercise

Abstract

Serum creatine kinase isoenzyme 2 concentrations (CK 2 mass) were measured in marathon runners during training and 1 and 2 days after a race and compared with values from 36 acute myocardial infarction (AMI) patients whose total CK and (or) CK 2 activities were similar to those of runners in the basal state. During training, runners had CK and CK 2 activities 53% and 43% above reference values, respectively, and 36% had CK 2 activity > 5% of total CK. Nine runners (26%) showed CK 2 mass values > 6 micrograms/L but < or = 10 micrograms/L; 35 of the AMI subjects, despite having CK activities similar to those of runners, had values > 10 micrograms/L. The ratio of CK 2 mass to total CK activity was significantly (P < 0.0002) different between sexes for runners. At 1 and 2 days after racing, 100% of CK and CK 2 activities and 71% and 57% of the percentages of CK 2 activity, respectively, were abnormally high; 57% and 43% of CK 2 mass values were > 10 micrograms/L, being comparable with those observed for the AMI group. Basal CK 2 mass values of the runners appeared only slightly higher than that for sedentary subjects, but after exercise half the subjects presented increased values similar to those observed for AMI subjects. The ratio of CK 2 mass to total CK activity appeared unaltered by exercise in all but one of the samples assayed, indicating its utility in evaluating CK 2 mass increases originating in skeletal muscle.

Short-Term Effects of Marathon Running in Master Runners: No Evidence of Myocardial Injury

“…In addition, individual post-race values were below reference values. Our data are in line with those reported by previous research with younger subjects [21,28,35] and confirm the utility of the CK-MB mass/total CK ratio in evaluating the source of high CK-MB levels associated to exertional rhabdomyolysis.…”

“…In this regard, there is little ques-tion that raised levels of this protein result from muscle trauma, especially after exercises largely involving eccentric contractions [11,21]. Our results, indeed, are in agreement with previous studies conducted with younger marathon runners [1,11,21,28]. Mass concentration of CK-MB, on the other hand, was within normal range before the marathon, although mean levels also increased in the samples collected after the competition.…”

“…Furthermore, reference levels were surpassed in postrace samples. Our results confirm those of previous studies conducted with younger subjects which have suggested that, after severe physical exertion, elevation of CK-MB mass may occur in healthy individuals not only above reference limits, but also into the range suggestive of myocardial damage [1,6,11,12,14,21,27,28]. In this regard, studies using myocardial imaging techniques suggest that serum CK-MB elevations probably do not reflect cardiac damage, but rather derive from skeletal muscle [27,31].…”

“…Although serum levels of some enzymes such as creatine kinase MB (CK-MB) might increase after prolonged exertion (i.e. marathon running) [1,6,11,12,14,21,27,28], the exact muscle source of released intracellular components is often difficult to interpret. Moreover, few reports have shown controversial results using more specific markers for detecting myocardial injury such as cardiac troponin T (TnT-c) or I (TnI-c) [1,9,11,12,20,21,25,26,32].…”

Effects of Vitamin-Mineral Supplementation on Cardiac Marker and Radical Scavenging Enzymes, and MDA Levels in Young Swimmers

“…Regular exercise and exercise training are important in both the primary and secondary prevention of diseases such as atherosclerosis, muscular dystrophy, and various heart diseases (24,29,30,53). One of the most important cardiac marker enzymes, Serum CK, has for years been measured and evaluated in exercise science as an essential parameter for the determination of muscular stress and various heart diseases (34,41). In the present study, post-exercise CK activities of male groups were higher than female groups, and they reached to 141 ± 7 U/L in the FCG, 156 ± 8 U/L in the MCG, 121 ± 6 U/L in the FSG, and 132 ± 7 U/L in the MSG.…”