title: Relationship between moderate intensity endurance training volume and natural killer cell cytolytic activity.
abstract: BACKGROUND
  This study was designed to examine the relationship between endurance training volume and natural killer cell (NK) cytolytic activity. We hypothesized that a dose dependent relationship exists between forced treadmill training volume and training induced increases in NK cell cytolytic activity.
  
  
  METHODS
  
  
  
  METHODS
  female, Swiss Webster mice were assigned to treadmill control (TC) or treadmill trained groups (n = 10 per group). Trained mice ran at 12 m per min. (8 degrees grade) for: 15 (EX15), 30 (EX30), or 60 minutes (EX60) per day, five days per week for 11 weeks. Splenic NK cell activity was expressed as median lytic unit (LU), median LU per asialo GM1 (AsGM1+) cell, and median LU per spleen.
  
  
  RESULTS
  Median NK activity was not significantly increased by training volume. A trend toward greater median LU per AsGM1+ cell was observed in EX30 group versus TC (p = 0.1). Training volumes less than or greater than this level produced smaller increases in NK cytolytic activity.
  
  
  CONCLUSIONS
  These data provide preliminary evidence indicating that training induced increases in splenic NK cell cytolytic activity do not exhibit a dose dependent relationship with treadmill training volume.
authors.affiliation: Department of Kinesiology and Leisure Studies, Washington State University, Pullman 99164-1410, USA.
authors.forename: E G
authors.initials: EG
authors.lastname: Lee
authors.forename: M E
authors.initials: ME
authors.lastname: Fox
authors.forename: G G
authors.initials: GG
authors.lastname: Meadows
authors.forename: E C
authors.initials: EC
authors.lastname: Johnson
authors.forename: S E
authors.initials: SE
authors.lastname: Blank
mesh_terms: D000818:Animals; D004305:Dose-Response Relationship, Drug; D005260:Female; D016130:Immunophenotyping; D007694:Killer Cells, Natural / Q000502:physiology*; D007958:Leukocyte Count; D051379:Mice; D008815:Mice, Inbred Strains; D010805:Physical Conditioning, Animal; D013154:Spleen / Q000166:cytology