Antibiotics are used for bacterial infections. The ingestion of antibiotics kills not only the bacteria that you are trying to rid your body of, but also kills the healthy bacteria that your body needs. To retain this healthy bacteria while ridding your body of the unhealthy type, refrigerate your antibiotics. If you are taking antibiotics for an infection, it is probably not a good time to train. You may diet, but exercise is not a good idea. Wait until your doctor releases you for exercise. Post antibiotic usage should be followed by a regime of L. acidophilus, B. bifidum, and B longum. These are the healthy bacteria that are necessary for good intestinal health. Do one to two sessions of these healthy bacteria post antibiotic treatment for faster recovery.