You dont feel like you used to. You sense some heart palpitations, shortness of breath and chest pain. Is it a heart attack? Well, youre not dead yet, so thats good. But you sure are concerned. And your loved ones are as well. You go to your doctor, they run a bunch of tests on you, and diagnose you with atrial fibrillation (or AFib as the cool kids call it. And since were cool kids, well stick with that term for the remainder of this article).
But why me?, you wonder. Why do bad things happen to good people? To beautiful people. Why cant bad things happen to bad and ugly people? (OK, maybe you dont say that part).
Besides the standard treatment for AFib (which is usually beta blockers and blood thinners, and occasionally surgeries like pacemakers and others), one of the most common recommendations is my friend exercise!
But youre an avid reader of my articles (arent you? ), so you know that exercise is good, but precise exercise is better. Exercise for type 2 diabetes is different than for high blood pressure, which is different than for osteoporosis, which is different than for you guessed it AFib.
So in this article, well talk about:
- What is AFib? What causes it
- How AFib is diagnosed
- The exercise prescription for AFib
Ready? Lets go.
But if you want help with your own AFib, we have a special program called Heart Healthy Exercise. If you want to see whether or not you qualify for that program, just fill out the application form on our home page.
Causes of AFib
Most things have more than one potential cause (and therefore, different treatments, based on the cause). In no particular order, here are some things that can cause AFib:
- Hyperthyroidism
- Diabetes
- Sleep apnea
- Overweight/obesity
- High blood pressure
- Extreme amounts of exercise
- but also lack of exercise.
- Smoking
and others.
Cardiovascular Exercise
Traditional treatment involves some combination of medications (usually beta blockers and/or blood thinners) or installing a pacemaker (an electronic device that sets the proper heart rhythm).
But either you dont want to go the traditional treatment route for whatever reason, or youre already on it, and you want to use exercise as an adjunct.
Im with you.
But to know the best course of action, we need to know some important details, like:
- Type: cardio vs. strength training
- Intensity: how hard
- Duration: how long
- Frequency: how many days per week.
So lets get to it.
Exercise is a double-edged sword. We think of it as more is better (more intensity, more frequency, more duration, etc.) But thats not necessarily the case.
Long-term high intensity cardio can actually predispose someone to AFib. In one study of over 52,000 cross-country skiiers, those with the best times also had the highest risk of AFib. But there is a difference between men and women. Long-term high intensity cardio is not great for men, but appears to be pretty good for women, according to this study.
And Im sure that you, my curious reader is wondering why? Why does high intensity exercise increase the risk of AFib compared to moderate intensity? There are a few possible explanations:
- We know that long-term, high-intensity, high-duration endurance training causes something called atrial fibrosis. Thats basically scar tissue on the heart. One study theorized that thats one of the reasons.
- More inflammation. Post-exercise inflammation is a good thing in general, since its the stimulus for more endurance the next time you exercise. But only to a certain point. Higher intensities produce higher inflammation, according to this study. Do this long enough, and you develop more inflammation that you need or more than is healthy.
- Worsened communication between the heart and the nervous system. One study showed that at higher intensities, theres a disrupted communication between the heart and the nervous system (thats called vagal tone). And the heart starts fluttering.
- Genes. Of course, we can never discount the effect of genes. The vast majority of people can do long-term, high-intensity cardio and never get AFib. But a minority of people who have the genetic predisposition will get it.
So thats on the prevention side of things. But what about treatment? Youre probably reading this article because either you or someone you know already has AFib.
How should you exercise when you already have it?
Thats where it gets a bit more confusing.
You know how I just spent a few paragraphs explaining how high intensity training isnt good for the prevention of AFib? Well, paradoxically, one study showed high intensity cardio to be effective for the treatment of AFib. Another study did too.
So what gives? What do we make of this? Is the solution to just chill? Grab a seat, and dont exercise?
And why am I showing you conflicting results? Because thats how science works. In the beginning stages of research, theres going to be lots of conflicting results, and rather than lying to you, and telling you that we know definitively how to exercise with AFib, the truth is more complex than that. The best we can say is that we have an idea, but we dont know for sure. In scientific lingo, its what they say more research is necessary.
But I dont have the time (years or decades) to wait for research to come out. I work with clients who have AFib now. How do I approach it? Heres what I make of this and my current recommendations about AFib:
- If the AFib happened in a young, healthy person due to too much high intensity exercise, for rehabilitation, I dont do more high intensity exercise. I go with moderate intensity.
- If the AFib happened in someone sedentary, who wasnt exercising, I choose either high intensity or moderate intensity. Or both. Start at moderate intensity for 2-3 months, and progress to high intensity.
For all the disagreement in research (is high intensity good or bad for AFib?), there is something that the different studies all agree on: moderate intensity is good. Its just a question of is high intensity better? But one thing that is clear is that moderate intensity is both safe and effective. So if in doubt, go with moderate intensity cardio.
Whats moderate intensity? Between 60-85% of your maximal heart rate. Your maximal heart rate is 220 minus your age. So if youre 70 years old, your max heart rate is 150. Youd exercise with a pulse of 60-85% of 150, or 90-128 beats per minute (bpm).
A number of studies have been done on different exercise protocols for AFib. They varied based on:
- Duration: in one study, people exercised as little at 24 minutes per workout, and as much as 90 minutes per workout in a different study.
- Frequency: in one study, people exercised as little as twice a week, and as much as 5 times a week in a different study.
So yes, theres what the research says, and I use that as a starting point to individualize the exercise prescription for each client. What Im looking for ultimately is approximately a 20-30% improvement in endurance (whether thats duration, speed or recovery) over a 3-4 month span.
Thats the how part of exercise how do I exercise? But what about the why part? By what mechanisms does exercise improve heart function in people with AFib? There are a few:
- Rate control. If AFib is the irregular beating of the heart, during exercise, the heart requires a pretty regular heartbeat. That heartbeat regularity carries over outside of exercise.
- Improvement in functional capacity: you have more endurance, so theres more that you can do in your day without getting tired.
- Necroptosis. I know, Im getting fancy on you there, with the lingo, but let me break it down. Necroptosis is simply the purposeful death of damaged heart cells. Cardio increases that.
- Atrioventricular conduction. The heart has 4 chambers. Two of them are called atria (plural or atrium singular), and two of them are called ventricles. For a nice, synchronized heart beat, the 4 chambers have to communicate with each other (via electrical signals). In AFib, there is worse communication between the 4 chambers, and thats why there can be an irregular heartbeat. Cardio helps improve the communication between the 4 chambers.
- Improved communication between the heart and nervous system. The brain is your hearts natural pacemaker. Just like theres communication between the 4 chambers of the heart with each other, theres also communication between the nervous system and the heart. If that communication is off, the heart can beat irregularly. Cardio can improve that communication as well.
Is there anything exercise cant do?
What About Strength Training for Atrial Fibrillation?
While there is very little research on strength training in people with AFib, there is a potential mechanism by which it could improve outcomes.
Aerobic capacity has 2 components: the central and the peripheral. The central component is the hearts ability to pump blood out to the extremities. The peripheral component is the ability of the muscles to extract oxygen from the blood.
So in theory, if we improve the muscles ability to extract oxygen, we can improve aerobic capacity as well.
Since almost no research is available, heres how I use strength training for people with AFib:
- Frequency: 2-3 days/week
- Number of sets: 2-3
- Number of reps: 15-20
- Number of exercises: 8-10 total.
What can you expect as a result of implementing the right exercise strategy if you have AFib? Pretty nice results like:
- A 20-30% improvement in your endurance.
- Not being out of breath as much.
- Ability to enjoy the activities you already like to do, whether thats hiking, tennis, or something else.
- More peace of mind that your ticker will keep on ticking properly.
- Lower risk of a heart attack and stroke.
- Potential avoidance or reduction of medications, if thats what youre looking for.
And that, in a nutshell is how you exercise with AFib. If all of this is overwhelming to you, and you want to personalize your exercise prescription (not to mention, nutrition and sleep) to your own body, we have a special program called Heart Healthy Exercise. If you want to see whether or not you qualify for that program, just fill out the application form on our home page.