Prescribing “the best medicine”

Are you exercising enough to prevent heart disease?

It can help you lose weight; decrease your blood pressure, cholesterol, and blood sugar; and reduce your stress. But wait, there's more: it also lowers your odds of a heart attack or other cardiovascular event and may even extend your life.

This wonder drug isn't a drug at all, of course — it's exercise. Yet only about half of all American adults do enough physical activity to benefit their health. And exercise is especially vital for people who are at risk for heart disease or already have it.

"Doctors are good at prescribing statins and aspirin, but we're not very good at prescribing one of the most powerful therapies available, which is exercise," says Dr. Hicham Skali, a cardiologist at Harvard-affiliated Brigham and Women's Hospital.

Expert advice

One issue is that doctors aren't always sure how to offer specific exercise advice to people with different heart-related conditions and risk factors. In the future, a new computer program developed by European cardiac rehabilitation experts may help. Called Exercise Prescription in Everyday Practice and Rehabilitative Training (EXPERT), the program prompts a clinician to enter information such as the person's age, weight, and resting heart rate, along with any health conditions and medications. The program then generates a tailored exercise routine that includes the type of exercise, intensity, frequency, and duration, along with any safety precautions.

For physicians, using this program could be a good way to get a conversation started, says Dr. Skali. But since most doctors don't have the tool (it still needs to be validated in a study), where does that leave you? During most office visits, doctors often don't have time for a detailed discussion about exercise. If you have specific exercise-related concerns, however, bring them up. Regular exercise improves many of the problems — especially diabetes and obesity — that contribute to heart disease. So be sure you know how much and how hard you should be exercising — and how to address any barriers that are keeping you from doing it, says Dr. Skali.

Enough exertion?

For people without heart disease, the American Heart Association recommends at least 150 minutes per week of moderate exercise or 75 minutes per week of vigorous exercise (or a combination of the two). Walking is often championed as a great way to get exercise, but check that you're actually walking briskly enough to raise your heart rate. "People will tell me, 'Well, I don't go the gym, but I'm pretty active — I do yard work and walk my dog every day,'" says Dr. Skali. But as people get older, their dogs tend to get smaller, and the outing ends up being more of a stroll than a brisk walk, he notes.

Wearable fitness trackers have made heart rate tracking popular in recent years. But you don't really need to measure your heart rate to know if you're exercising hard enough. Instead, Dr. Skali recommends paying attention to your rate of perceived exertion, or RPE (see "Talking while walking: Assessing your effort"). Aim for an exertion level around 5 or 6 — about halfway between sitting still and exercising as hard as you possibly can. Start slowly and build up to 30 minutes a day, five days a week. As your fitness level improves, you may be able to save time by adding short bouts of more vigorous activity. As a general rule of thumb, one minute of vigorous-intensity activity counts about as much as two minutes of moderate-intensity activity.

Focusing on RPE also makes sense if you take a beta blocker, which helps lower blood pressure and slows the heart rate. Common examples include metoprolol (Lopressor, Toprol) and atenolol (Tenormin). People often notice that their heart rate does not rise as high during exercise after they start taking these drugs and may wonder if they're exercising at the right intensity. It's fine to go by how you feel rather than trying to reach a certain target heart rate, says Dr. Skali.

Alternatives to walking

For people who have low back pain or creaky knees or hips, walking may be difficult. Swimming, doing water aerobics, or using a recumbent bike may be better options. Walking may also be painful for people with narrowed arteries in the legs, a problem known as peripheral artery disease (PAD). However, walking is as effective as — and less risky than — getting a leg artery stent, a tiny mesh tube to open up the artery. Even if your calves hurt after walking just one block, take a rest, recover, and repeat. Eventually, you'll be able to walk farther without pain.

Talking while walking: Assessing your effort

Use this "rate of perceived exertion" (RPE) scale to gauge whether you are exercising intensely enough.

Scale

Intensity

Breathing/speaking pattern

1

Extremely easy

Restful breathing; able to sing

2

Very easy

Can easily speak in complete sentences

3

Easy

4

Easy to moderate

Speech becomes broken

5

Moderate

Breathing becomes heavier

6

Talking is difficult

7

Moderate to vigorous

Deep, forceful breathing, but still sustainable

8

Vigorous

Labored breathing; cannot talk

9

Very labored breathing; borderline breathless

10

Very vigorous

Gasping for air

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