Among the proteins that were more expressed in the practitioners of the physical exercise group, lactotransferrin has bactericidal properties [34], S100-A8 protein has antimicrobial activity, and lactoperoxidase has antimicrobial properties, helping defend the host in the airways against infections [35], whereas galectin-3 binding protein is associated with the immune system, stimulating the host's defense against viruses and tumor cells [36, 37], in addition to participating in the regulation of inflammatory processes and the immune response [38]. Here, LTF is linked to infection.