Biomaterial Database

The relationship of serum creatine kinase, fiber type, and isometric exercise. 1982

P M Clarkson, and W Kroll, and J Graves, and W A Record

In 11 untrained subjects (mean age = 22.5 yr) serum creatine kinase (CK) was measured before and after two types of knee extension exercise regimens. One regimen consisted of 35 10-s maximal isometric contractions separated by a 20-s rest (10:20). This regimen provided adequate recovery time between trials so that strength loss amounted to only 23.4% over the 35 contractions. The other exercise regimen consisted of the same 35 maximal isometric contractions but separated by 5 s between trials (10:5), resulting in a 54.6% strength loss. Muscle fiber type was also determined to assess the relationship of fiber type with serum CK and strength loss. The fast-twitch (FT)/slow-twitch (ST) area ratio correlated with resting CK. Baseline strength correlated with strength loss over the 10:5 condition but not with strength loss over the 10:20 condition suggesting different mechanisms responsible for strength decline for the two exercise conditions. Although a greater strength loss was found for the 10:5 condition, serum CK levels were significantly higher following the 10:20 exercise. An analysis of covariance showed that the mean strength level over the 35 contractions was significantly related to CK increase in the two exercise conditions. Results suggest that mechanical factors associated with high tension levels may be responsible for CK efflux following isometric exercise.

UI	MeSH Term	Description	Entries
D007537	Isometric Contraction	Muscular contractions characterized by increase in tension without change in length.	Contraction, Isometric,Contractions, Isometric,Isometric Contractions
D008297	Male		Males
D009119	Muscle Contraction	A process leading to shortening and/or development of tension in muscle tissue. Muscle contraction occurs by a sliding filament mechanism whereby actin filaments slide inward among the myosin filaments.	Inotropism,Muscular Contraction,Contraction, Muscle,Contraction, Muscular,Contractions, Muscle,Contractions, Muscular,Inotropisms,Muscle Contractions,Muscular Contractions
D009132	Muscles	Contractile tissue that produces movement in animals.	Muscle Tissue,Muscle,Muscle Tissues,Tissue, Muscle,Tissues, Muscle
D003402	Creatine Kinase	A transferase that catalyzes formation of PHOSPHOCREATINE from ATP + CREATINE. The reaction stores ATP energy as phosphocreatine. Three cytoplasmic ISOENZYMES have been identified in human tissues: the MM type from SKELETAL MUSCLE, the MB type from myocardial tissue and the BB type from nervous tissue as well as a mitochondrial isoenzyme. Macro-creatine kinase refers to creatine kinase complexed with other serum proteins.	Creatine Phosphokinase,ADP Phosphocreatine Phosphotransferase,ATP Creatine Phosphotransferase,Macro-Creatine Kinase,Creatine Phosphotransferase, ATP,Kinase, Creatine,Macro Creatine Kinase,Phosphocreatine Phosphotransferase, ADP,Phosphokinase, Creatine,Phosphotransferase, ADP Phosphocreatine,Phosphotransferase, ATP Creatine
D005082	Physical Exertion	Expenditure of energy during PHYSICAL ACTIVITY. Intensity of exertion may be measured by rate of OXYGEN CONSUMPTION; HEAT produced, or HEART RATE. Perceived exertion, a psychological measure of exertion, is included.	Physical Effort,Effort, Physical,Efforts, Physical,Exertion, Physical,Exertions, Physical,Physical Efforts,Physical Exertions
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000328	Adult	A person having attained full growth or maturity. Adults are of 19 through 44 years of age. For a person between 19 and 24 years of age, YOUNG ADULT is available.	Adults