How quickly your heart rate returns to normal after strenuous exercise can be a key indicator of heart health, and a recent study found that regular exercise can improve your heart rate recovery (HRR) within just a few months. The results are important because research shows individuals with a healthy HRR live longer than those with an abnormal HRR, in which the heart takes longer to slow down to a normal rate.
The study, published in the Sept. 26 issue of Circulation: Journal of the American Heart Association, was led by Leslie Cho, MD, co-section head of Preventive Cardiology and Rehabilitation and director of the Womens Cardiovascular Center at Cleveland Clinic. Dr. Cho explains that heart rate recovery is a measure of how well your autonomic system is working. To calculate your HRR, take the number of your heart beats per minute at peak exercise and subtract the number of beats per minute just two minutes after you stop exercising. If the difference is greater than 12 beats per minute then you are okay, she says.
Dr. Cho and her colleagues studied more than 1,000 patients going through cardiac rehabilitation. They found that, on average, patients who completed 12 weeks of cardiac rehab increased their HRR from 13.2 to 16.6 beats per minute.
The study also revealed that of the patients who had an abnormal HRR of 12 beats per minute or less, 41 percent normalized after completing cardiac rehab. Given the significance of improving HRR as a means of boosting cardiovascular health and extending life, you might think cardiac rehab participation is popular.
But only 10 percent to 20 percent of candidates for cardiac rehabilitation participate in structured exercise programs, Dr. Cho says. Cardiac rehabilitation is the most underused treatment in America, she adds. Not enough doctors are recommending it to patients. Even when a recommendation is made, patients arent informed that cardiac rehabilitation can help them live longer.
She notes that no drug can do for your heart what regular exercise can do. Cardiac rehab usually has patients attend workouts three days a week for 12 weeks. Patients programs are individualized and they are monitored by rehab specialists during the sessions. The programs also include education on diet, lifestyle modification, medication adherence and how to continue an effective exercise program once the formal rehab program ends.
Its really important to encourage our patients to participate in structured exercise, not just telling the patient to go exercise and do your best and good luck, Dr. Cho says. All of our patients in the study were in a cardiac rehab phase 2 program, which means most of the exercise was cardio, and they exercised for about 50 minutes a day. The intensity of the exercise was individualized.
Abnormal HRR Risks
Abnormal HRR has been linked with death, MI and major adverse cardiovascular event, Dr. Cho explains.
Patients in the study who didnt improve their heart rate recovery tended to be older, with a history of diabetes, peripheral artery disease and congestive heart failure.
The risk of dying within eight years more than doubled in patients whose HRR was abnormal after cardiac rehabilitation, even after adjusting for factors such as smoking and changes in the use of medications.
Dr. Cho says the next step in this research is to determine whether patients who still had abnormal HRR after rehab would benefit from continued cardiac rehab.