Aerobic exercises such as running help your muscles get stronger. Regular and consistent exercise does cause micro tears in muscle fiber, but that is nothing to worry about. The recovery happens on your rest days and it also allows your muscles to grow stronger. The same holds true for the heart, which is perhaps the most vital muscle in the body. Experts recommend regular running to build endurance and also control risk factors such as blood pressure, cholesterol, and blood sugar for cardiovascular diseases. In short, it can do wonders for your heart health.

But how do you know if you are fit to run? And how much running is enough to keep the heart healthy? 

How does running improve your heart health?

Running benefits everyone, young and old, lean and obese, as well as people with chronic health conditions. Along with the lungs, it trains the heart to pump blood more effectively, enabling more oxygen to get to the muscles and organs, thus improving overall health.  

Running regularly and consistently can improve your heart health.

Let’s look at some of the changes that occur. 

1. Research shows that over time, running strengthens your heart muscle and its ability (especially of the left ventricle) to pump oxygen-rich blood through the aortic valve to the rest of the body

2. The resultant improved pumping of the blood then enhances blood flow and oxygenation of tissues in the body

3. Running also reduces arterial stiffness, which further brings down the imbalance between the free radicals and antioxidants in the body, thereby reducing possibility of any form of chronic heart ailment. It also prevents inflammation of blood vessels

4. Running improves blood circulation, reduces the risk of blood clots, brings down blood pressure, fights bad cholesterol or low-density lipoprotein (LDL), and increases good cholesterol or high-density lipoprotein (HDL). All these reduce the risk of cardiovascular diseases

5. Running also reduces/ stabilizes the resting heart rate, which improves blood flow to the coronaries (blood vessels of the heart)

The graph below illustrates how running reduces the risk of cardiovascular diseases.

How much running is good for your heart health?

The American College of Sports Medicine recommends that healthy adults between the age group of 18 and 64 must participate in moderate-intensity aerobic physical activity (which includes running) for minimum 30 minutes, five days a week, or 20 minutes of high-intensity aerobic physical activity thrice a week. However, you need to ascertain your own fitness levels to know what intensity of aerobic activity or running works best for you. 

How do you know you are fit to run?

If you have been following a sedentary lifestyle, it’s unlikely that you’d be able to switch to and sustain high-intensity running. Focus on progressing gradually. Before taking up any strenuous physical activity, it is essential to know how healthy your heart is. If you are suffering from any illness or chronic health condition, do consult your doctor and take all the necessary precautions before you lace up.  

There are multiple ways to know your heart better. Here’s a checklist:

Know more about yourself

• Was there any episode of chest pain or tightness in the chest? Or any fainting episodes in the past?
• Does your heart race abnormally fast? Are there any irregular or missed heartbeats during exercise? 

Know about your family

• Has anybody in your family died below the age of 50 due to unknown reasons?    
• Does any member of your immediate family have hypertension or any other heart disease? Genetics play an important role in ascertaining the chances of premature heart disease. 

Consult your physician

• Get your health check-up done if you have any known heart disorders, hypertension, or a family history of sudden deaths, illnesses, or are taking any medication. A check-up would include testing your blood profile, undertaking electrocardiogram, an echocardiography, and stress test.

Get adequate rest

• Schedule your recovery periods, allow your body to rest and recover in between high mileages. A well-balanced diet and adequate hydration will help you recover faster. 

And finally, listen to your heart and know your resting heart rate (RHR).

What is RHR?

According to the American Heart Association, your RHR is the number of times your heart beats every minute when you are not active. Many factors influence your RHR such as age, weight, medication, time of the day, caffeine intake, and sleep.

Also read: Why Is Running Good for You?

What is a sound RHR for runners? 

The ideal time to check your RHR is when you wake up in the morning. You may check your heart rate by putting your finger on the wrist (radial artery) or the side of the neck (carotid artery). Count the number of heartbeats over a full minute. 

RHR above 90 suggests lower levels of fitness, overtraining, dehydration, fever, or fatigue. Additionally, high RHR could be due to high blood pressure 

Ideally, you will begin seeing changes in your RHR within two to three weeks of consistent running. Use your RHR as a guide in your training. 

The body gives signals when it feels overwhelmed by a high-impact exercise like running. It puts a strain on the heart so it is important to not overtrain, because any kind of prolonged stress on the heart could cause health problems.

When to seek medical help

Get immediate medical help if you have any of the following signs:

• When you experience excessive shortness of breath. If you are untrained to tackle it, it will go away with consistent training
• When you experience chest pain. It could be due to chest muscle cramps, but will be more localized, or because of dehydration, heartburn
• When you experience palpitations
• If you faint
• When you experience an unusual amount of fatigue
• If you are unable to complete your workouts
• When you experience unusual sweating

While evidence suggests a heightened risk of cardiac events during high-intensity exercise, the likelihood of such events is ultimately very, very low. There is a lot of research about the advantages of running and exercise and how it boosts heart health. The benefits far outweigh the risks, but do make an informed decision, and take one step at a time. Never rush. 

References
1. Huppin L. What The Research Reveals About Blister Prevention In Ultra Endurance Runners. Podiatry Today. https://www.podiatrytoday.com/blogged/what-research-reveals-about-blister-prevention-ultra-endurance-runners#:~:text=After four days of running,72 percent after day three (accessed Apr 9, 2021).
2. All About Heart Rate (Pulse). Heart. https://www.heart.org/en/health-topics/high-blood-pressure/the-facts-about-high-blood-pressure/all-about-heart-rate-pulse (accessed Apr 9, 2021).
3. Kang S-J, Kim E-H, Ko K-J. Effects of aerobic exercise on the resting heart rate, physical fitness, and  arterial stiffness of female patients with metabolic syndrome. J Phys Ther Sci 2016; 28: 1764–8.