Shing CM, Peake JM, Suzuki K, Okutsu M, Pereira R, Stevenson L, Jenkins D, Coombes JS - 33126 N - J Appl Physiol 2006 ; 34p.
The aim of this study was to investigate the influence of low dose bovine colostrum protein concentrate (CPC) supplementation on selected immune variables in cyclists. Twenty-nine highly-trained male road cyclists completed an initial 40-km time trial (TT40) and were then randomly assigned to either a supplement (n=14, 10g bovine CPC per day) or placebo group (n=15, 10g whey protein concentrate per day). Following five weeks of supplementation, the cyclists completed a second TT40. They then completed five consecutive days of high-intensity training (HIT) that included a TT40, followed by a final TT40 in the following week. Venous blood and saliva samples were collected immediately before and after each TT40 and upper respiratory illness symptoms were recorded over the experimental period. When compared to the placebo group, bovine CPC supplementation significantly increased pre-exercise serum soluble tumor necrosis factor receptor 1 during the HIT period (bovine CPC=882+/-233pg/ml, placebo=468+/-139pg/ml; P=0.039). Supplementation also suppressed the post-exercise decrease in cytotoxic/suppressor T cells during the HIT period (bovine CPC=-1.0+/-2.7%, placebo=-9.2+/-2.8%, P=0.017) and during the following week (bovine CPC=1.4+/-2.9%, placebo=-8.2+/-2.8%, P=0.004). Bovine CPC supplementation prevented a post-exercise decrease in serum IgG2 concentration at the end of the HIT period (bovine CPC=4.8+/-6.8%, P=0.88; placebo=-9.7+/-6.9%, P = 0.013). There was a trend towards reduced incidence of upper respiratory illness symptoms in the bovine CPC group (P=0.055). In summary, low dose bovine CPC supplementation modulates immune parameters, which may have contributed to the trend toward reduced upper respiratory illness in the bovine CPC group.