Immune changes: 2 h of continuous vs. intermittent cycling.
Immune changes following 2 h of intensive cycling with or without rest intervals were measured in trained cyclists (n = 12) who functioned as their own controls during two test sessions that were separated by two weeks. Subjects cycled for 2.0 h at approximately 64 % Watts(max) continuously (C) or with 3-min rest intervals (R) interspersed every 10 min (2.6 h total time), with the order of the sessions randomized. Blood samples were collected 30-min pre-exercise, and immediately and 1-h postexercise, and assayed for blood leukocyte subset counts, plasma IL-6, IL-10, IL-1ra, IL-8, PHA-induced lymphocyte proliferation, and natural killer cell activity (NKCA). Significant time effects were measured for all immune measures, but no significant differences in the pattern of change were found between C and R exercise trials. In conclusion, immune changes induced by 2 h of intense and prolonged exercise paralleled those measured when athletes rested 3 min every 10 min of exercise.
Nieman
D
D
Department of HLES, Appalachian State University, Boone, NC, USA. niemandc@appstate.edu
Henson
D
D
Gojanovich
G
G
Davis
J M
JM
Dumke
C
C
Utter
A
A
Murphy
A
A
Pearce
S
S
McAnulty
S
S
McAnulty
L
L
D000328:Adult; D001642:Bicycling / Q000502:physiology; D016207:Cytokines / Q000097:blood / Q000276:immunology; D005080:Exercise Test / Q000379:methods; D006801:Humans; D007107:Immune System / Q000502:physiology*; D007694:Killer Cells, Natural / Q000276:immunology; D008214:Lymphocytes / Q000097:blood / Q000276:immunology; D008297:Male; D005082:Physical Exertion / Q000502:physiology*; D014481:United States
D016207:Cytokines