Listen to Your Heart Target Heart Rate The Target Heart Rate is the heart rate range that you should try to achieve and maintain during your exercise. Your fitness level determines which of the three power levels you should maintain; Beginner, Intermediate or Advanced. For each power category allow for four to six weeks to pass before moving to the next level. This is presuming that you exercise at least three sessions a week. Your heart rate should be measured every fifteen minutes for athletic participants of aerobic exercise and every five to ten minutes for beginners. Begin counting within five seconds after exercise stops. Count the number of beats for ten seconds then multiply by six to get the beats per minute. If the heart rate is too low, increase your activity and include more arm movement. On the other hand, if the heart rate is too high, decrease the activity and reduce or eliminate arm movement. During pregnancy, heart rates should not exceed 140 bpm. There are two methods for calculation of the target heart rate. The standard method uses an intensity range of 60% to 90% of the maximum heart rate. The Karvonen method incorporates the individuals resting heart rate and is therefore the more accurate method. This method uses an intensity range of 50% to 85%.