Hypertrophic cardiomyopathy (HCM) is a genetic condition that makes the heart’s left ventricle thick and stiff. It prevents blood from circulating well. HCM doesn’t always cause noticeable symptoms. But it’s one of the most common causes of sudden cardiac death in people under 35 (including young competitive athletes).

People with HCM are naturally left wondering whether they should avoid physical activity altogether. Studies show that only around 45 percent of those with HCM get enough physical activity. But if you’re careful, you can still enjoy the benefits of exercise to improve your health and quality of life with HCM.

Learn How To Monitor Your Target Heart Rate

Cardiologists (heart doctors) used to tell people with HCM not to exercise, but that guidance has changed. Doctors now advise people with HCM to speak with their healthcare providers about finding the right exercise program based on their needs. After all, physical activity helps people with hypertrophic cardiomyopathy avoid the heart problems associated with a sedentary lifestyle, like hypertension (high blood pressure), obesity, and high cholesterol.

It’s crucial to work with your cardiologist on an individualized exercise prescription. Overall, the American Heart Association encourages regular exercise for people with HCM. However, some people need to be monitored before starting an exercise program. Your cardiologist may want you to stick to a certain level of exercise intensity, depending on your condition.

One way to measure exercise intensity is by the percent of heart rate reserve (HRR). Your HRR is calculated by subtracting your resting heart rate from your maximum predicted heart rate. Resting heart rate describes how many times your heart beats per minute when resting (like first thing in the morning before getting out of bed).

You can get an idea of your maximum predicted heart rate by subtracting your age in years from the number 220. You can then simply subtract your resting heart rate from your maximum heart rate to get your heart rate reserve.

To measure your heart rate:

1. Firmly press the three middle fingers of one hand against your wrist, neck, elbow, or the top of your foot. Apply enough pressure that you can feel a gentle pulsing sensation.
2. While watching a clock or timer, count how many beats you feel for 30 seconds.
3. Double that amount, and you’ll know your heart rate per minute.

You could also use one of the more high-tech alternatives to measure your heart rate. For instance, some wearables — like an Apple Watch or a chest strap created for fitness monitoring — can help you keep a digital record of your heart rate that you can then share with your cardiologist.

Once you know your HRR, you can monitor how you feel during different levels of exercise and stick to the goals your healthcare provider recommends for you.

If you’re not sure how to calculate your heart rate reserve or want reassurance, ask your healthcare provider for help at your next follow-up visit. Although it’s a good way to start knowing your body better, this method isn’t always accurate. A cardiopulmonary exercise test (CPET) or stress test is the best way to evaluate your risk and determine what kind of exercise is best for you.

People with HCM often take beta-blockers, and that makes HRR methods less useful. Doctors prefer to create exercise plans by evaluating each person individually and deciding together what’s best, rather than using fixed numbers.

Ask Your Cardiologist About Safe Exercises

Once you know your target HRR and you have a way to track it, you can create a safe exercise plan with your cardiologist. Exercise doesn’t necessarily mean you have to get involved in competitive sports — your exercise plan can be tailored to your own preferences and abilities. However, many people with HCM can participate in vigorous exercise with their doctor’s approval after a comprehensive risk evaluation. Also, competitive sports aren’t universally restricted anymore, but you should assess your risk and seek medical counseling before choosing to play them.

Everyone with HCM will have different exercise recommendations based on their abilities and limitations. But some good general guidelines for safe exercise include:

• Warming up first to increase your heart rate gradually
• Starting with shorter periods of activity and working your way up to longer workouts
• Not holding your breath when lifting weights or working out
• Not changing positions rapidly, like going from lying down to standing
• Choosing consistent movement over fast bursts, alternating intense activity and rest
• Taking time to cool down and return to a resting state when you finish

Consider Your Environment

If you’re anxious about exercising with HCM, picking the right setting and conditions for exercise can give you peace of mind. It’s a good idea for people with any type of heart disease to avoid exercising in extreme temperatures, especially cold and windy weather.

People with HCM may have arrhythmias (irregular heart rate) that, in some cases, may lead to sudden cardiac arrest. Fortunately, a device called an automated external defibrillator (AED) allows others to administer lifesaving shocks to the heart if an emergency occurs.

Many public places have AEDs readily available and require staff to undergo training so they’re ready to jump into action if needed. Before joining a gym or other exercise facility, ask if they have a defibrillator and staff who know how to use it.

Some people with HCM have an implantable cardioverter defibrillator or permanent pacemaker to help control an irregular heart rhythm. If you have either, you may feel more comfortable informing the staff of your exercise facility about your condition. You can also wear a medical ID bracelet or keep a special card in your wallet that alerts others to your heart condition if you become unconscious or experience an adverse event.

Exercising with a partner, in group classes, or places with other people around ensures you’re not alone if you need help. If you start noticing unusual symptoms while exercising, like shortness of breath, lightheadedness, or chest pain, you can take a break, knowing that others are around if you need assistance.

Track Your Starting Point and Goals

If you have HCM, be mindful of your starting point when beginning a new exercise routine. If you’re new to exercise or haven’t worked out for a while, you’ll want to take it slow and pay attention to how you feel.

Pace yourself when increasing the frequency, intensity, duration, or type of exercise you’re doing. You can also keep a detailed log of the exercises you performed and your resulting heart rate changes so you can continually share it with your cardiology provider and ensure that your exercise plan is on the right track.

Finally, always be sure to get regular checkups and keep your doctor informed about any changes to your exercise plan. You may want to start with exercise supervised by a physical therapist or through a cardiac rehab program. A stress test that monitors your heart rate during exercise will give your cardiologist a better idea of your current exercise capacity so you can observe changes over time.

Exercise isn’t just good for heart health. It’s also good for your mental well-being. People with HCM can enjoy recreational exercise with shared decision-making and guidance from their healthcare team. Instead of staying “on the bench,” find out your risk factors and safe level of aerobic exercise so you don’t get left out.

Talk With Others Who Understand

MyHeartDiseaseTeam is the social network for people with heart disease and their loved ones. On MyHeartDiseaseTeam, more than 62,000 members come together to share stories with a community of people who understand life with hypertrophic cardiomyopathy and other types of heart disease.

How has hypertrophic cardiomyopathy affected your exercise training habits? Which low- or moderate-intensity exercise routines do you prefer? Share your experience in the comments below, or start a conversation by posting on your Activities page.