Side Effects. Side effects are rare; still symptoms like ear irritation, acute inflammation of the ear canal and pinna are reported. In some cases the pet might experience lack of appetite, vomiting, diarrhea, or hearing loss during the course of treatment, which might require immediate medical aid.
Furthermore, if the median age of a marathon participant is about 40, then the average maximum heart rate of a U.S. marathoner is about 180. Seventy percent of 180 is 126, while 80 percent is 144. Therefore, the heart rate of a mid-pack runner during a marathon is near the middle of the range -- between 126 and 144, or 135 beats per minute.
Your heart rate should remain at 60 to 70 percent of its maximum heart rate, which at age 30 is between 114 and 133 beats per minute and at age 55 is between 99 and 116 beats per minute. During these runs, your heart learns how to better pump blood to your muscles.