Bovine colostrum is the first milk secreted by cows after calving. Colostrum is high in protein and contains a number of bioactive substances including growth and antimicrobial factors. Antimicrobial factors in bovine colostrum include immunoglobulin and a variety of other less specific antimicrobial proteins and peptides. Immunoglobulin and other antimicrobials are important for immune system function. This is important to athletes because intense exercise training can compromise the immune system; therefore bovine colostrum has potential to improve exercise performance by preventing immune system dysfunction that is common during periods of heavy exercise training .