ESCANABA - At your doctor's office, the nurse puts her fingers on your pulse after taking your blood pressure. At the gym, you may stop the treadmill now and then to check the carotid artery in your neck. Heart rate is an important measure of your exercise intensity as well as your overall health. Do you know your resting heart rate and what it means? Do you understand about target heart rates during exercise? In terms of health, recovery heart rate may be the most important of all.
Heart rate refers to how many times the heart beats every minute pumping blood to every cell in the body. The pumping is done by the left lower chamber of the heart, which must be healthy enough to sustain the effort, minute after minute, day after dayabout 100,000 beats a day, 37 million beats a year.
Resting heart rate refers to the number of beats the heart is making when you're resting. The best time to take your resting heart rate is when you first wake up in the morning, preferably before you get out of bed. Count the beats for a full 60 seconds. The number you get will be a bit higher once you stand up, but that's okay. The most important thing is that you take your pulse the same way every day. The ideal resting heart rate for an adult is 60 to 100. Generally, it's best to be at the lower end of the range.
It makes sense that a healthy heart is capable of accomplishing its task more efficiently. And studies have found that persons with lower heart rates are not only fitter but tend to live longer.
If you're just starting an aerobic exercise program, it's a good idea to take your resting heart rate every morning and track the trend. You can expect a steady drop over the first six to eight weeks. That means that you are getting fitter, with a more efficient and healthy cardiovascular system. If your resting heart rate suddenly goes up 10 or 15 beats some morning without explanation, it may be a sign that you are training too hard and would benefit from a rest.
When you're working out, you may notice your heart beating faster; that's normal. The goal of aerobic exercise is to raise your heart rate and keep it there for an extended period.
For maximum benefit, most trainers recommend a target heart rate of 65 to 85 percent of maximum heart rate. As a rule of thumb, maximum heart rate can be determined by subtracting your age from 220 if you are a male or 226 if you are a female. In other words, a 40-year-old female has a maximum heart rate of 186 and should work out at an intensity between 121 (65 percent) and 158 (85 percent) beats per minute. A heart rate of 50 percent of maximum (93 beats) will give a lower intensity, though still beneficial, workout.
Most persons who exercise regularly can usually tell by perceived effort alone whether they are working out at low, moderate or high intensity. The higher the intensity, the more labored the breathing. If you use the carotid artery to determine your heart rate during exercise, take it for 10 seconds and then multiply by 6. Another good method is to use a heart rate monitor to guide your exercise.
In terms of cardiovascular health, one very important factor is how quickly your heart recovers after a strenuous workout. This is known as recovery heart rate.
Complete recovery back to your resting heart rate may take several hours after even a moderate workout. But what you're looking for is how much your heart beat slows during the first minute or two of rest. The quicker your heart rate comes down, the better. If your heart rate comes down 22 to 52 beats during the first two minutes, your biological age is about the same as your calendar age. If it's less than that, you may have health problems.
One study found that a reduction of the heart rate of less than 12 beats during the first minute after exercise was a "powerful and independent predictor of the risk of death."
Smoking, drinking a lot of caffeine, anemia and thyroid disorders can elevate heart rate. A resting heart rate that is consistently high even at the high end of normal is reason to see your doctor.
If you notice a flutter, a flip flop or a missed beat or two while you're taking your pulse, it's probably nothing to worry about. Nearly everyone has an irregular beat from time to time. An irregular rhythm, though, is more serious. A substantial number of veteran endurance athletes develop atrial fibrillation, a heart arrhythmia.
Particularly during the early stages, atrial fibrillation (afib) strikes intermittently. You may have only occasional episodes when workouts become very difficult. Until you see a doctor, it's probably a good idea to limit the intensity of your workouts.
(EDITOR'S NOTE: Health Update appears weekly in the Daily Press and features local health professionals. Dr. Rubright is a board certified family practice physician with OSF St. Francis Hospital & Medical Group. He sees patients at the OSF Medical Group Clinic in Gladstone.)