The Effect of Bovine Colostrum Supplementation on Fitness, Muscle Mass, Inflammation and Immune Function, During the Regular Season, in Rugby Players

Bovine colostrum is the first milk secreted by cows after calving. Even though bovine colostrum has similar protein content as regular milk, it contains greater levels of anti-microbial substances and growth factors. Intense training may compromise the immune system; therefore, colostrum has potential to improve exercise performance by preventing immune system dysfunction that is common during periods of intense training. PURPOSE: The purpose was to determine the effect of 8 weeks of bovine colostrum supplementation in comparison to soy protein supplementation, on rugby players’: body composition, strength, endurance performance, vertical jump height, and IgA, IL-6, IL-1β and C reactive protein levels, during the regular rugby union season. METHODS: Twenty-nine rugby union players (n=3 female) were randomized into two groups (double blind); Group 1 received 38g/d of protein from bovine colostrum, and Group 2 received 38g/d of protein from soy. Before and after the 8 weeks of supplementation, participants were evaluated for IgA, IL-6, IL-1β and C reactive protein levels from salivary samples, body composition using dual energy X-ray absorptiometry, muscle thickness of their quadriceps and biceps using ultrasound, bench press and leg press strength, vertical jump height, and aerobic fitness using the Leger maximal multistage 20-m shuttle run field test. RESULTS: There were no differences between groups over time in all variables other than vertical jump height. There was a significant group x time interaction for vertical jump (p=0.002) with the colostrum group (+0.9cm) increasing more than the soy group (-0.5cm). CONCLUSION: BC supplementation in rugby union players during the regular season did not affect body composition, salivary immune markers level and fitness components (excluding vertical jump height) in comparison to soy protein supplementation. Bovine colostrum supplementation may enhance leg power to a greater extent than soy protein supplementation