Plasma zinc and immune markers in runners in response to a moderate increase in training volume.
Changes in plasma zinc concentration and markers of immune function were examined in a group of 10 male runners (n = 10) following a moderate increase in training over four weeks. Seven sedentary males acted as controls. Fasting blood samples were taken at rest, before (T0) and after (T4) four weeks of increased (+ 16 %) training and after two weeks of reduced (-31 %) training (T6). Blood was analysed for plasma zinc concentration, differential leucocyte counts, lymphocyte subpopulations and lymphocyte proliferation using incorporation of 3H-thymidine. The runners increased their training volume by 16 % over the four weeks. When compared with the nonathletes, the runners had lower concentrations of plasma zinc (p = 0.012), CD3 + (p = 0.042) and CD19 + lymphocytes (p = 0.010) over the four weeks. Lymphocyte proliferation in response to Concanavalin A stimulation was greater in the runners (p = 0.0090). Plasma zinc concentration and immune markers remained constant during the study. Plasma zinc concentration correlated with total leucocyte counts in the athletes at T6 (r = -0.72, p < 0.05) and with Pokeweed mitogen stimulation in the nonathletes at T6 (r = -0.92, p < 0.05). Therefore, athletes are unlikely to benefit from zinc supplementation during periods of moderately increased training volume.
Peake
J M
JM
School of Human Movement Studies, University of Queensland, St Lucia, QLD 4072, Australia. jpeake@hms.uq.edu.au
Gerrard
D F
DF
Griffin
J F T
JF
D000222:Adaptation, Physiological / Q000276:immunology*; D000328:Adult; D015415:Biomarkers / Q000097:blood*; D006304:Health Status; D006801:Humans; D007958:Leukocyte Count; D008214:Lymphocytes / Q000378:metabolism; D008297:Male; D010806:Physical Education and Training / Q000379:methods; D012420:Running / Q000502:physiology*; D015032:Zinc / Q000097:blood*
D015415:Biomarkers; D015032:Zinc