Examining the effects of colostrum in rugby players presents a unique scientific opportunity because of the nature of their training regime. Rugby players' early season workouts are the most stressful training sessions of the season (after the winter break they must condition quickly for the start of the season with few if any pre-season games and their workouts involve repeated sprint activity in addition to weight training). Rugby players would be most susceptible to overtraining and immune system depression during this time of the year. Bovine colostrum with its high levels of anti-microbials and other bioactive factors may be beneficial to mitigate the deleterious effects of early, high intensity training.