You, or someone you know had a heart attack. It’s now behind you, and you want to get back to your daily life as fast as possible, and prevent that from ever happening again. The good news: you’re alive. The bad news: if you don’t change something about your life, the future isn’t bright:
- You’ll be tired all the time, which could affect the amount of things you’re able to get done in your day
- A heart attack could change your heart’s rhythm, requiring regular trips to your cardiologist
- You have a chance of getting another heart attack in 5 years or less.
That’s if you don’t change something about your life. But, if you take your heart attack for what it is (a warning sign), and make some necessary changes, you can live a long and healthy life afterwards.
In this article, we’re going to cover:
- What happens to your body after a heart attack
- The 3 factors that predict both the quality and quantity of life after a heart attack
- How soon you should start exercising after a heart attack
- The guidelines for exercise for heart attack survivors
- One warning sign that you can find during exercise, that tell you to see a doctor immediately
If you, or someone you know has had a heart attack, and you want to take all the guesswork out, and get a program specific to you, we have a specific program called the “Healthy Heart Program.” If you’re interested, just email me, with the words “Healthy Heart Program” in the subject line.
What Happens to Your Body After a Heart Attack
You live your life, humming along, your ticker is ticking, and you never really think about how it works. Then, you have a heart attack. Your ticker stops ticking.
Often, the reason that happens is due to a blockage in the arteries (the blood vessels sending blood away from the heart). It’s not the only reason, but it sure is the most common one.
Blood contains oxygen, so if no blood is getting to the heart, no oxygen is getting there, either. Without oxygen, we start to die. And that’s what happens to the heart muscle after a heart attack – it starts to die, but not completely.
Just as other muscles contract, so does the heart (since it’s a muscle). However, a muscle that is partially dead can’t contract with the same force as a muscle that is working just fine. If it can’t contract with the same force, it can’t deliver as much blood to the rest of the body as a healthy heart. So in medical jargon, “cardiac output” is decreased. Usually, it’s decreased by 30-50%.
If it’s decreased by 30-50%, you can bet that you’ll have 30-50% less energy.
One other thing that happens after a heart attack is the amount of blood that the heart pumps with each beat is decreased (that’s called your “ejection fraction.”) An ideal ejection fraction is around 60%, give or take about 10%. That is, with each beat, your heart pumps out 60% of the blood that it has (or more precisely, 60% that just one of its chambers has – the left ventricle. There are 3 other chambers, and ejection fraction does not refer to them).
After a heart attack, ejection fraction decreases, possibly as low as 35%.
Here are some other changes that happen to the heart after a heart attack:
- The part of the heart that got “attacked” (in medical terms, “infracted”) gets thinner and longer, so it can’t contract as hard.
- You get scar tissue on your heart. Scar tissue is strong, but it doesn’t allow full expansion of the muscle. So the heart becomes stiffer.
As a result of this, quality of life certainly declines:
- For one thing, if you were an active person before the heart attack, and liked to play tennis, hike, etc., your capacity to carry out those activities will be limited
- You’ll also have constant anxiety about another heart attack – not fun
- Any time you get chest pain, you might think another heart attack is coming on
- You might get dizzy, and sweat without much effort
- You might get pain in your legs, or they might swell up
…and other undesirable symptoms.
Fortunately, the more serious and aggressive you are about the recovery, the better your quality of life will be afterwards. It’s not inconceivable that with the proper approach, your life post heart attack may actually be better than your life before the heart attack.
The 3 Factors That Predict the Quality and Quantity of Life After a Heart Attack
After a heart attack, what people often want to know is “how much do I have left to live?” and “what will my quality of life be like afterwards?” Valid questions.
Fortunately, there are 3 factors that help answer those questions:
- Ejection fraction. As mentioned in the previous section, this is how much blood does your heart pump out with each beat. It should pump out 62% of its blood with each beat. The lower it is, the higher the probability of an early death, as well as poor quality of life
- Degree of adequacy of blood supply to the heart (this is called “myocardial ischemia”). The less blood you get to the heart, the more likely you are to suffer an early death.
- The single best predictor of both quality and quantity of life after a heart attack: your cardiovascular fitness. In the cardiovascular research, they use a unit called “METs” – metabolic equivalents. If your fitness is tested to be below 4 METs, your likelihood of early death is very high. I know that using METs is not helpful outside of a laboratory. So how does it convert to “real life?” If someone can’t walk at a pace of approximately 4 miles per hour (that’s a fast walk) for a prolonged period of time, well… that’s not good.
While it’s still controversial whether exercise and nutrition has any effect on ejection fraction, what’s clear (and obvious) is that exercise and proper nutrition certainly help improve blood supply to the heart, and exercise is pretty much the only thing that can improve cardiovascular fitness, making it a first-line treatment post-heart attack.
How Soon Should You Start Exercising After a Heart Attack
You know those old school recommendations of “oh, you had a heart attack – you should take it easy.” Well, taking it easy only speeds up your passage outta here. Better do the opposite – get on the bike, and start pedaling.
So how long after a heart attack can you exercise? That’s what the researchers in this meta analysis wanted to find out. They accumulated studies that began exercise at 4 different time periods:
- Evolving: under 6 hours after a heart attack
- Acute phase: 6 hours-7 days after a heart attack
- Healing phase: 7-28 days after
- Healed phase: 29 or more days after
What the researchers found was that if exercise was initiated in the 6 hour-7 day period, people recovered much better than if they began after 7 days.
According to the previous meta analysis, if exercise is begun 6 hours – 7 days after a heart attack, the undesirable changes (weakening and stiffening of the heart) don’t occur to the same extent. Whereas, if someone waits for a month or more, some irreversible changes will have occurred by then, like the deposition of excess connective tissue on the heart, making it stiffer than before the heart attack.
The immediate question is “doesn’t exercise so soon after a heart attack increase the risk of another heart attack?” Fortunately, the researchers did not find that to be the case.
In the “clinical implications” of that meta-analysis, the researchers state that
Most rehabilitation post-myocardial infarction [that’s medical terminology for “heart attack] programs start at least four to six weeks after hospital discharge… early exercise training could attenuate left ventricular remodeling and improve cardiopulmonary capacity in patients with myocardial infarction after hospital discharge (around 1 week).
So there you have it – you should be exercising within 1 week of having a heart attack.
Guidelines: Exercise for Heart Attack Survivors
Now we know that you shouldn’t wait for a long time after a heart attack before exercising. But what do you actually do? As I emphasize in my other articles on chronic conditions (like diabetes, high blood pressure, osteoporosis, anxiety, depression, and others), there needs to be specificity in exercise prescription. Just saying “exercise is good” is not enough. It’s missing important details like:
- What type of exercise – cardio or strength training?
- Intensity – how hard?
- Frequency – how many times per week?
- Duration (for cardio – how long) or volume (for strength training – how many sets and repetitions)
We need the same level of specificity in exercise prescription for people who want to start exercising after a heart attack. Should you be taking it easy with the exercise? Should you use a lower intensity?
The answer quite clearly is “no.” A higher intensity is actually required to have the beneficial effects on the heart. Translation: just going for a leisurely walk is not good enough (unless the walk makes you huff and puff).
One study compared 2 exercise intensities: moderate intensity (65-85% of maximal heart rate), and high intensity (over 85% of maximal heart rate). What they found was that high intensity improved their cardiovascular fitness more than moderate intensity. But this was more than 1 week after a heart attack.
So in the first week, I wouldn’t do vigorous exercise after a heart attack, but over time, raise the intensity, to get the beneficial changes we talked about earlier.
What about weight lifting? That’s what one study wanted to find out – should you just do cardio, or should you also do weight lifting after a heart attack? To answer that question, researchers divided participants into 2 groups:
- Group 1: only cardio, at 65-85% of maximal heart rate)
- Group 2: cardio (same as above) plus weight lifting
The results: the group that did cardio AND weight lifting had improved ejection fractions. The group that did only cardio did not improve ejection fraction.
If you’re wondering “how long should I exercise each time?”, ideally the answer comes from numerous studies that have done head-to-head comparisons of different exercise durations, like 30 minutes vs. 60, or 20 vs. 40, etc. Unfortunately, such a study has not yet been done (at least to my knowledge). But the studies that do show improvements in cardiovascular health after a heart attack had people exercising for 20-60 minutes.
The frequency recommended by the American College of Sports Medicine (ACSM) is at least 4 times per week.
So there you have it – your heart attack exercise recommendations:
- Type: cardio and weight lifting
- Intensity:
- For cardio: over 65% of your maximal heart rate
- For weight lifting: 30-70% of your max
- Duration: 20-60 minutes
- Frequency: 4 times per week
Perhaps as more research becomes available, these heart attack exercise recommendations will change, but as it stands right now, this is the gold standard.
A Word of Warning
You’re now on your way to better heart health, so you’re exercising after a heart attack on a regular basis, using the guidelines I put forth in this article. But there is one thing to be very cautious about: your blood pressure.
It should rise during exercise. That’s normal, and in fact, desirable. It should not shoot through the roof, but it should rise (the degree of the rise will depend on the intensity). The problem happens if it actually fails to rise, or even falls.
If this happens, you should stop your workout, and go to see a doctor immediately.
So there you have it – some general guidelines on how you should be exercising after a heart attack.
Now yes, there may be additional factors to consider, like stents, medications, etc., but fortunately I cover how medications affect exercise in this article.
If you, or someone you know has had a heart attack, and you want to take all the guesswork out, and start to exercising after a heart attack properly, you can get a program specific to you. We have a specifial program called the “Healthy Heart Program.” If you’re interested, just email me, with the words “Healthy Heart Program” in the subject line.
