title: Creatine kinase levels during preseason camp in National Collegiate Athletic Association Division I football athletes.
abstract: OBJECTIVE
  To investigate mean creatine kinase (CK) levels in National Collegiate Athletic Association (NCAA) Division I football athletes and the relationship between mean CK levels and demographic variables.
  
  
  METHODS
  Observational cohort.
  
  
  METHODS
  NCAA Division I football program.
  
  
  METHODS
  NCAA Division I football athletes.
  
  
  METHODS
  Blood and urine samples were obtained from 32 athletes on the first (time 1), third (time 2), and seventh (time 3) days of football camp.
  
  
  METHODS
  Mean CK levels. The hypotheses were formulated before the data were collected.
  
  
  RESULTS
  All urine samples tested negative for blood. Mean CK levels were 284.7 U/L at time 1, 1299.8 U/L at time 2, and 1562.4 U/L at time 3. The increases in means were statistically significant (P < 0.005 for all pairwise comparisons). Most demographic variables were not related to mean CK levels. The number of days in the precamp conditioning program was negatively associated with mean CK levels (P = 0.0284).
  
  
  CONCLUSIONS
  Mean CK levels in NCAA Division I football athletes during camp were higher than the serological criteria for rhabdomyolysis commonly used in clinical practice. More data are needed to assess if the number of days of participation in precamp conditioning is related to lower CK levels in NCAA Division I football athletes during camp.
authors.affiliation: *Department of Family Medicine; and †Institute for Orthopaedics, Sports Medicine & Rehabilitation, The University of Iowa Carver College of Medicine, Iowa City, Iowa; ‡Department of Biostatistics, The University of Iowa College of Public Health, Iowa City, Iowa; §Department of Orthopaedics & Rehabilitation, The University of Iowa Carver College of Medicine, Iowa City, Iowa; ¶Department of Athletics, The University of Iowa, Iowa City, Iowa; ‖Department of Internal Medicine, The University of Iowa Carver College of Medicine, Iowa City, Iowa; and **Department of Epidemiology; and ††Program of Hospital Epidemiology, The University of Iowa Hospitals and Clinics, Iowa City, Iowa.
authors.forename: M Kyle
authors.initials: MK
authors.lastname: Smoot
authors.forename: Joseph E
authors.initials: JE
authors.lastname: Cavanaugh
authors.forename: Annunziato
authors.initials: A
authors.lastname: Amendola
authors.forename: Douglas R
authors.initials: DR
authors.lastname: West
authors.forename: Loreen A
authors.initials: LA
authors.lastname: Herwaldt
mesh_terms: D015331:Cohort Studies; D003402:Creatine Kinase / Q000097:blood* / Q000652:urine; D005538:Football / Q000293:injuries*; D006801:Humans; D008297:Male; D064797:Physical Conditioning, Human; D012206:Rhabdomyolysis / Q000097:blood* / Q000652:urine; D014495:Universities
chemical_list: D003402:Creatine Kinase