‘Exercise Is Medicine’ -- Here's Why

If you’ve been to the doctor over the last several decades, you’ve likely been told about the importance of exercise to your heart and overall health. You’ve likely also been encouraged by your doctor to exercise regularly. Have you ever wondered why exercise contributes to good health?

Eli Friedman, M.D., medical director of sports cardiology at Miami Cardiac & Vascular Institute, says that exercise is medicine for the mind, body and soul.

“Exercise lowers blood pressure, blood glucose, and bad cholesterol,” he said. “It lowers risk factors for cardiovascular disease across the board. It also improves eating, sleeping, feeling better and one’s mental health. There are very few instances where we would advise someone not to exercise.”

A study published in 2015 in the Scandinavian Journal of Medicine & Science in Sports indicated that 26 different chronic diseases could be treated with prescribed exercise. The diseases fall into the following categories:

• Psychiatric, such as depression and anxiety
• Neurological, such as dementia and Parkinson’s disease
• Metabolic, such as diabetes and high cholesterol
• Cardiovascular, such as hypertension and coronary heart disease
• Pulmonary, such as COPD, or chronic obstructive pulmonary disease, and asthma
• Musculoskeletal, such as osteoarthritis and osteoporosis

Also, a global health initiative launched by the American College of Sports Medicine and the American Medical Association in 2007 aims to encourage healthcare providers to assess patients’ physical activity and prescribe exercise as a key treatment in the clinical management of chronic diseases.

Health Benefits of Exercise

“In terms of cardiovascular health, exercise engages the cardiovascular system and improves its efficiency,” Dr. Friedman said. “When you exercise regularly, your blood pressure decreases, your resting heart rate goes down and your metabolism increases.”

Dr. Friedman adds that both aerobic exercise – what most people refer to as “cardio” – and resistance, or strength, training contribute to improved health. Cardiovascular exercise, such as running, jumping, swimming and cycling, gets your heart beating, blood pumping, your lungs moving and your brain signals firing. Strength training, such as weightlifting and resistance movement, improves your bone and muscle health, making each more agile and efficient in using the necessary nutrients needed to perform. 

How Much Exercise Is Recommended?

Dr. Friedman says the “dose” of recommended exercise for most adults is 150 minutes per week of moderate aerobic exercise. He defines “moderate” as being able to carry on a conversation with someone while exercising. He and the American Heart Association say this amount can be replaced by 75 minutes of high-intensity aerobic exercise each week. Dr. Friedman notes that this higher level of intensity makes it difficult to carry on a conversation other than with “yes” or “no” answers. The American Heart Association also recommends moderate- to high-intensity muscle-strengthening activity at least twice a week.

“If you aim for and hit these numbers, you maximize the benefits of exercise,” Dr. Friedman said. “In most people, there’s really no such thing as too much exercise.

When Is Exercise Too Much?

As a sports cardiologist, though, Dr. Friedman also works closely with elite and professional athletes and sometimes sees issues arise when exercise is pushed to its upper limits. For these individuals, it’s important to have a physician monitoring their exercise and nutrition to ensure optimal health. But, for most people, exercise within the recommended limits is beneficial.

Still, Dr. Friedman says to be on the lookout for the following symptoms, which can indicate problems, when you exercise:

• Breathing that is far more difficult than what activity being performed should require.
• Chest pain or pressure, or a burning, stinging or stabbing sensation in the chest.
• Less tolerance for exercise than you previously had.
• Feeling lightheaded or dizzy or passing out.
• Experiencing a racing heartbeat or the sensation of the heart skipping.

If you experience these symptoms, contact your doctor, or if the symptoms are severe, call 911 immediately, Dr. Friedman advises.

Exercise After COVID-19

Since studies about the effects of COVID-19 have indicated a possible link between the novel coronavirus and heart damage, Dr. Friedman recommends that people who have recovered from COVID-19 should discuss their gradual return to physical activity and exercise with their primary care physician or cardiologist. In most mild cases of COVID-19 that didn’t require any treatment, he says, wait the 10-14 days of recovery recommended by the U.S. Centers for Disease Control and Prevention (CDC) and slowly return to activity. If symptoms arise seek further evaluation from a healthcare provider.

Some of the effects of COVID-19 noted in these studies include an inflammation of the heart muscle, or myocarditis, which can lead to heart failure and arrhythmias or irregular heartbeats. In some patients, COVID-19 also led to blood clots that affect the lungs, heart attacks and strokes. Still others experienced pericarditis, in which the sac that surrounds the heart becomes inflamed or filled with fluid (pericardial effusion) and puts pressure on the heart, preventing it from functioning properly.    

“The vast majority of people with mild symptoms from the virus, especially those with symptoms that affected only areas above the chest and did not involve fever, chest pain, shortness of breath or hospitalization, should be able to return to moderate exercise as soon as they feel well enough to do so,” he said. But, hospitalization, especially with evidence of heart damage may require a slower return to activity and management by a cardiologist.

Dr. Friedman says that physical activity and exercise that is proportionate to each person’s ability can be beneficial. To determine your ability and the level at which you should exercise safely and with maximum heart and health benefits, he recommends talking to your doctor or healthcare provider.

“My goal is getting as many people as possible to exercise safely,” he said. “For most people, the more exercise you do, the better your heart functions and your overall health improves. If you don’t exercise, talk to your doctor about how to start, and if you do exercise, don’t stop. Take your daily dose of exercise. It’s the best medicine.”