Vassilis Mougios1. 1. TEFAA, University of Thessaloniki, 541 24 Thessaloniki, Greece. mougios@phed.auth.gr
Abstract
BACKGROUND: The serum concentration of creatine kinase (CK) is used widely as an index of skeletal muscle fibre damage in sport and exercise. Since athletes have higher CK values than non-athletes, comparing the values of athletes to the normal values established in non-athletes is pointless. The purpose of this study was to introduce reference intervals for CK in athletes. METHOD: CK was assayed in serum samples from 483 male athletes and 245 female athletes, aged 7-44. Samples had been obtained throughout the training and competition period. For comparison, CK was also assayed in a smaller number of non-athletes. Reference intervals (2.5th to 97.5th percentile) were calculated by the non-parametric method. RESULTS: The reference intervals were 82-1083 U/L (37 degrees C) in male and 47-513 U/L in female athletes. The upper reference limits were twice the limits reported for moderately active non-athletes in the literature or calculated in the non-athletes in this study. The upper limits were up to six times higher than the limits reported for inactive individuals in the literature. When reference intervals were calculated specifically in male football (soccer) players and swimmers, a threefold difference in the upper reference limit was found (1492 vs 523 U/L, respectively), probably resulting from the different training and competition demands of the two sports. CONCLUSION: Sport training and competition have profound effects on the reference intervals for serum CK. Introducing sport-specific reference intervals may help to avoid misinterpretation of high values and to optimise training.
BACKGROUND: The serum concentration of creatine kinase (CK) is used widely as an index of skeletal muscle fibre damage in sport and exercise. Since athletes have higher CK values than non-athletes, comparing the values of athletes to the normal values established in non-athletes is pointless. The purpose of this study was to introduce reference intervals for CK in athletes. METHOD: CK was assayed in serum samples from 483 male athletes and 245 female athletes, aged 7-44. Samples had been obtained throughout the training and competition period. For comparison, CK was also assayed in a smaller number of non-athletes. Reference intervals (2.5th to 97.5th percentile) were calculated by the non-parametric method. RESULTS: The reference intervals were 82-1083 U/L (37 degrees C) in male and 47-513 U/L in female athletes. The upper reference limits were twice the limits reported for moderately active non-athletes in the literature or calculated in the non-athletes in this study. The upper limits were up to six times higher than the limits reported for inactive individuals in the literature. When reference intervals were calculated specifically in male football (soccer) players and swimmers, a threefold difference in the upper reference limit was found (1492 vs 523 U/L, respectively), probably resulting from the different training and competition demands of the two sports. CONCLUSION: Sport training and competition have profound effects on the reference intervals for serum CK. Introducing sport-specific reference intervals may help to avoid misinterpretation of high values and to optimise training.
Authors: Gerhard Schumann; Roberto Bonora; Ferruccio Ceriotti; Pascale Clerc-Renaud; Carlo A Ferrero; Georges Férard; Paul F H Franck; F Javier Gella; Wieland Hoelzel; Poul Jørgen Jørgensen; Takashi Kanno; Art Kessne; Rainer Klauker; Nina Kristiansen; Jean-Marc Lessinger; Thomas P J Linsinger; Hideo Misaki; Mauro Panteghini; Jean Pauwels; Heinz G Schimmel; Arlette Vialle; Gerhard Weidemann; Lothar Siekmann Journal: Clin Chem Lab Med Date: 2002-06 Impact factor: 3.694
Authors: Ana Luisa Miranda-Vilela; Arthur K Akimoto; Graciana S Lordelo; Luiz C S Pereira; Cesar K Grisolia; Maria de Nazaré Klautau-Guimarães Journal: Eur J Appl Physiol Date: 2011-04-23 Impact factor: 3.078
Authors: Ana Luisa Miranda-Vilela; Graciana Souza Lordelo; Arthur Kenji Akimoto; Penha Cristina Zaidan Alves; Luiz Carlos da Silva Pereira; Maria de Nazaré Klautau-Guimarães; Cesar Koppe Grisolia Journal: Genes Nutr Date: 2011-04-11 Impact factor: 5.523
Authors: Oliver Ludwig; Joshua Berger; Torsten Schuh; Marco Backfisch; Stephan Becker; Michael Fröhlich Journal: J Sports Sci Med Date: 2020-08-13 Impact factor: 2.988
Authors: Ana Luisa Miranda-Vilela; Arthur K Akimoto; Graciana S Lordelo; Luiz C S Pereira; Cesar K Grisolia; Maria de Nazaré Klautau-Guimarães Journal: Eur J Appl Physiol Date: 2011-06-26 Impact factor: 3.078