In this episode of the Athletes Compass podcast, hosts Paul Warloski and Dr. Paul Laursen, along with Marjaana Rakai, delve into the topic of atrial fibrillation (AFib) and its impact on endurance athletes. They discuss the symptoms, causes, and risks associated with AFib and other heart issues like ventricular tachycardia, drawing from personal experiences and expert insights. Emphasizing the importance of a balanced training approach, the hosts explore the relationship between mid-zone training and heart health, and offer practical advice on how athletes can monitor their heart condition and seek appropriate medical care.

Key Takeaways

  • Symptoms of AFib: Fluttering in the chest, fatigue, palpitations, and dizziness.
  • Causes and Risks: Large return of blood to the heart, electrical events in the atria, and high levels of mid-zone training.
  • Prevalence in Athletes: AFib and related heart issues are more reported in older male athletes but can affect anyone.
  • Importance of Medical Attention: Early detection and medical intervention are crucial for managing AFib.
  • Training Recommendations: Adopting a polarized training approach with balanced low and high-intensity sessions to reduce heart stress.
  • Personal Experiences: Hosts share their encounters with heart issues and the importance of listening to one’s body.

Full Transcript

Paul Warloski (00:28)

Hello and welcome to the Athletes Compass podcast where we navigate training, fitness and health for everyday athletes. You know, our goal on this podcast is to help everyday athletes improve their health and fitness so they can improve their performance over time. However, sometimes our health can go sideways because or due to our training. Paul, can you talk to us about what AFib is or atrial fibrillation?

Paul Laursen (00:56)

Yeah, yeah, this is a, this one, I don't know. So I follow Paul the, a lot of the forums in particular, you know, of course the Athletica forum, but I also follow more traditionally the Slow Twitch forum. And I know a lot of our endurance athletes will probably be on that one as well, but I cannot get over the number of, you know, reports of different heart issues that people are expressing. Most notably, actually, I'll just start,

Paul Warloski (01:06)


Paul Laursen (01:24)

So two of my heroes, two of the big four that used to be called, Scott Tinley and Dave Scott are both going in. As we speak, they're probably actually, as we're recording, they're on the table for open heart surgery, for aortic aneurysms. We'll get to those ones later, but the ones that's more reported in athletes, and I just pull up, here's the most recent post, just came through literally minutes ago from Slow Twitch.

was this is in AFib and here's like, here's what's the guy reported. The guy, I run MD reported, in a gravel race. He was feeling great, strong up to miles 65, 70, and then he started feeling a fluttering in the chest and just an overall, I don't feel so good. Thought it might be electric light imbalance or my hydration was off. put, you know, pushing a little bit more made me aware of this weird chest sensation.

So I pushed pretty easy for the rest of the race, pretty smart. So that he was encountering this, this aphid, atrial fibrillation. My dad has this as well as an older, older gent that's just winding down in his cycling years. So yeah, it kind of like, what are we talking about here? We can certainly see some symptoms, right? But it's, there's this...

palpitations or fatigue and fluttering that's kind of experiencing in, you're experiencing in the chest. And so we should also go back and say, well, when we talk about atrial fibrillation, we're talking about the upper chambers of the heart, the atrias. Remember you've got your atrias are the upper chambers and you got your ventricles, which are the lower chambers. So this is for some reason, something in the art, the upper chambers starts to go off a little bit.

and they take the whole thing out of sync. Now if you go back more to that, that guy's thread, it's taking a long time for the heart to slow itself down. So it really gets kind of out of whack. So yeah, I mean, why is this occurring? And why is this occurring a little bit more in athletes?

Paul Warloski (03:36)


Paul Laursen (03:40)

Hard to actually know, but it's like there's this big return of blood that's often happening into these chambers. And that potentially also with health aspects that we can talk on a little bit later contributes to some sort of these erratic oscillations. And remember that there's electrical events that are going in here. So for some reason, the electrical events of the heart and particularly those in the atria,

are out of sync all of a sudden. So maybe you guys have any experiences, Paul, Marjaana, yourself with this occurrence of AFib?

Paul Warloski (04:24)

Well, I have had similar problems, mine are not AFib, mine are ventricular tachycardia, which is the similar instances, but in the ventricles as opposed to in the atrias. And it's kind of the surly older brother of AFib in terms of it can be a little bit more serious and it can bring on more of an attack. But it tends to be...

a little bit more subdued. I don't have it all the time. It just pops up. One of the things that happened though, once I discovered, and this just happened last year when I turned 60, I noticed once I put it out on the social media is so many people, especially men, responded, yes, I have AFib. Yes, I've had VT and it's been very similar.

So is there a prevalence in endurance athletes compared to the general population that you've known of?

Paul Laursen (05:37)

Well, it's, so I revert, just disclaimer, I'm no expert in this, but I revert to my colleague who's very famous, Dr. Phil Maffetone, who's wrote a, just a section on this in the Hit Science textbook on the athlete's, the athlete heart and sudden athlete death. And his,

thinking was that, well, in fact, the prevalence might not necessarily be greater, but it's more, you know, it's more, these events get purported in the media a lot more. So, you certainly hear about them a lot because it's kind of unexpected, right? You don't think that an athlete is going to have any of these sorts of issues.

The other point I just reviewed the section in the book Phil also makes is that there's often an underlying health issue that might be predisposing the athletes to this. Again, we always think that our athletes are the healthiest of beings. They look that, but there can be within the insides, there can still be these issues that...

that have accumulated over years. And so, yeah, I think the question is, Paul, is we don't really know, but there's certainly differences in how the heart would behave, especially when we look to our athletes that are pushing a lot of mid -zone training. It seems that mid -zone training is the likely culprit.

of these occurrences and potentially the, you know, when these sort of, not sorry, not just the occurrence, but how this kind of comes about. And especially if we look to Dave Scott, Scott Tinley, or under the knife right now as we speak, you think about these guys throughout their life, right? Think of how much mid -zone kind of training they probably were doing. They were, you know, diesel engines, probably very good at it, raced a lot.

And, you know, anecdotally, when you read, you listen to some of their social media platforms, they're still kind of going at a later age. A lot of just a lot of pushing for, and they're, you know, for many, many years. And that's a lot of work on the heart, right? And so, and again, if we look to both, it's just, it's amazing. The two of the big four are in the same boat.

going under for surgery at the same time, it's quite uncanny, but it's, you know, they have aortic aneurysm. So in their situation, the aorta has distended so much so that it's, yeah, it could actually burst. If they don't get this surgery, it can actually burst. So that's, again, think about the pressure that's always happening in the...

in the aorta there. In the case of the, the AFib, again, we've got all this backflow of blood that's coming into the atrius that maybe doesn't occur as much in the general population that isn't exercising. So yeah, there's certainly big differences, Paul, in, you know, the overall behavior of the blood flow to the heart in an athlete versus a sedentary individual.

And maybe it's this type, specifically these incidences are more prevalent because why would these sorts of things occur in individuals that aren't getting large blood flows to their heart? The other point that Phil makes is that despite these issues that we see and are highly purported, it shouldn't be something that stops us from exercising.

And that's really important. We see them a lot, and especially because we're all glued to social media and the like, they come in our face, but the same principles still apply, a balanced, holistic approach to training with health first as we purport throughout the Athletica companies.

Paul Warloski (10:14)

Thank you.

Paul Laursen (10:21)

This still makes most sense to be best practice out there. And yes, these things might occur, but just be aware, listen to your body, screening, all these sorts of things should kind of save you in the end.

Marjaana Rakai (10:37)

Yeah. And I think, like for listener, keep in mind that, oftentimes as endurance athletes, we're so in tuned with our bodies. We know our, you know, strong heart muscle that has, gotten stronger and larger. Our, look, resting heart rate is usually a lot lower than a normal population. And we kind of like, we've, we can feel.

any arrhythmia or any abnormality a lot sooner than a regular population who don't exercise, right? I have three leaky valves, apparently. But the doctor that I saw, he said nothing to worry about, just keep checking it every couple of years. And I've heard like for women as we...

approach menopause and after menopause, when our estrogen is lower, that we should always get our like a two year heart check just to monitor our heart health. But what is it about specifically intensity around that mid zone, zone three, like between that nice zone two and then the high intensity that we do.

above the threshold that is so loading for heart health.

Paul Laursen (12:06)

Yeah, it's a great question. And again, I'm just guessing, right? Like with a bit of experience behind me. And it's probably you're close towards your max stroke volume. So for a long time, right? Remember when we ride in our zone two or L2 below or below, you know, the heart's working, but it's not, the stroke volume isn't towards maximal.

Marjaana Rakai (12:09)

Mm -hmm.

Paul Laursen (12:35)

And then when we start to get into zone three, we'll call it mid zone and four and five, there's this big kick in stroke volume. And remember that, I guess mid zone sort of training, if we're performing a lot in there or towards threshold, your stroke volume is really kicking up there. The blood flow is really kind of kicking up there. And I...

Again, I'm just kind of guessing, but I'm imagining that that's just a lot more of a heavy hammer on the heart because it's just really starting to get that big, big load of blood flow through it, right? Which is so critical for performance. And no question we want to have that happening when we're racing. And we do need to prepare for that as well. But...

Paul Warloski (13:32)

Thank you.

Paul Laursen (13:33)

I guess it's just, you know, we have to be mindful of that and balance it out. Not to say you shouldn't do it, but it's just, you know, I don't, you certainly, certainly is a strong suggestion that, you know, kind of a more polarized approach to your training might be a healthier sort of option so that you're getting

you know, the majority of your training, in the, the lower ends of the stroke volume, right? Remember the stroke volume is how much blood the heart beats every, every beat. And, and then, you know, just, but so the bulk kind of at a lower level, but then also don't forget your high intensity work where you're, you're going to get a really give the heart a good, a good jolt, but it's there'll be recovery between that. Right. so this is why we want those recovery days. Like.

Marjaana classic example, she's just done some big training over the weekend and we're just talking now before the podcast about how she's going to go into this real recovery moment that Gordo Byrn spoke about on the Training Science podcast. And we've done lots of little clips to promote those things where he's really, yeah, you know, you bulk in that training load, but then make sure you really, you know, the recovery days are also just as important so that the body kind of heals himself there.

and conversely, you, you know, in the, maybe the thing that you don't want to do is go back and start doing more mid zone sort of thing, because you sort of can, that's the crazy thing is that we are, equipped as human beings to keep that mid zone training. You can almost kind of do it day in day out. You burn yourself out. It leads to over training. We know that, but here's another thing where we're guessing total guests, but it's probably a contributor to,

Paul Warloski (15:15)

Thank you.

Paul Laursen (15:32)

the unhealthy athlete profile, and potentially some of these occurrences of arrhythmias and the various different heart health issues that we're speaking about here in the podcast.

Paul Warloski (15:35)

Thank you.

So the more polarized model would be better because the high intensity is shorter and we do less of it, but we still get the benefits that we need for the training stimulus.

Paul Laursen (15:57)

Yeah, that's for sure. I mean, there's a time and place for the mid -zone training, certainly for principles specificity when you're building up to your gravel race or your Ironman or your 70 .3, et cetera, et cetera, but maybe not all the time, right? And yeah, it's kind of, we need to sort of swing through the various different blocks. And again, back to Gordo Burr and those recovery blocks, recovery periods.

Paul Warloski (16:16)

Mm -hmm.

Paul Laursen (16:28)

are just as important as the specific quality stuff that we're talking about.

Paul Warloski (16:36)

I noticed that last summer when I.

problems, the ventricular tachycardia. I noticed a, you know, I started noticing there was a problem when I started getting dropped when, when my heart was causing problems. are there issues that you have noticed with an athlete's performance in terms of how they, how they, perform in, in, in racing or in training?

Marjaana Rakai (17:12)

How do you feel like when you're having VT?

Paul Warloski (17:17)

So the first thing that I start to feel is the fluttering in my heart as if my heart starts to beat. And then I can start to see it on my device, on my Garmin that my heart rate is starting to increase. In fact, Garmin just told me as while we were talking here that I had a really big training week last week because my heart rate was at 180 and 190 and 200 for several rides. Because my heart issues are back. We've talked about.

that before I had an ablation last fall that seemed like it, like it cured. And then they came back doing an interval a couple of weeks ago. And, you know, I did some rides last week and definitely the big thing that I noticed is that I just can't go very hard because a, my heart is pounding and any kind of effort. I ended up slowing down. Like I did a,

three hour ride yesterday at 15 miles an hour, which is okay. But for me, that's pretty slow and I don't feel as good. So there's definitely a change I'm having to make. Doing group rides, I'm not really able to do them because I'm riding that slowly. I'm talking with my doctor a lot and he says, as long as you're feeling okay.

that when the heart rate goes up, that's okay. It's not ideal, obvious, but I'm not going to have a problem. It's when I start to feel faint, if I start to feel faint, if I start feeling lightheaded, any kind of chest pain, obviously, those are bigger warning signs where I need to call it a day and stop. But I'm facing maybe not racing, at least not at a harder level. I'm just going to be riding my bike, which is okay.

But it's definitely going to be an adjustment.

Have we seen any kind of sex or age difference in the development of AFib or any of these heart issues?

Paul Laursen (19:27)

Yeah, for sure, Paul. Unfortunately, you're right in the category of higher risk. So it tends to be more males that get this and tends to be older athletes as well, right? So more time on tension ultimately as older athletes. And I think probably the male incidence probably tends to be because there is...

or at least there has been in the past, more males engaged in these sorts of endurance activities. It's probably changing a little bit now, but yeah. So yeah, currently that's where that sort of hits. But yeah, no, I think that that was similar advice that was given to my dad as well, was you can still kind of go out there and do that, but you really have to be aware of how you're feeling.

And especially if you start to get lightheaded, you got to know when to call these sorts of things. And especially if you're talking on a bike, right? You're on a moving vehicle that can go to speed. So you got to be certainly careful in that context. And then, of course, how else can we?

you know, make further assessments, Paul. So I would imagine, Paul, you've been hooked up to one of those electrocardiogram devices in, you know, either in your doctor's office or in a clinician's office that he's referred you to.

Paul Warloski (21:07)

Yeah, last week I actually had one and they what they do for that is look for for structural issues and to make sure that there aren't structural problems and that it's still just an electrical problem. And because those are two different things, if there were structural issues, it would be a it would be a different story. But those are clean for me, which is good. It's just, you know, I have a slightly.

you know, enlarged heart, you know, because of being an athlete and that's, you know, it's good. and it's functioning well. It just gets off the rails sometimes.

Paul Laursen (21:46)

Yeah, for sure. So yeah, I was doing a little bit of research on this, what we tend to see in your ECG, electrocardiogram. Again, remember hooked up 12 lead ECGs. We tend to see like a flat or depressed P wave, right? So it's the P -QRS complex. So I guess the voltage is going through the atria to make the atria's top chambers contract.

It just kind of, it's usually depressed or flat lines. We just don't see much action happening there. Right. So, and you can just imagine, imagine if the atrias, the top chambers aren't really contracting. This is in AFib. I think this is different than you, Paul, but in AFib, a lot of most people are kind of talking about those atrias are just sort of not engaged. So, and maybe that's why you get this flutter response, right? It's the ventricles in the, that are fluttering and working. It's like, you know,

It's like, hey, give me some blood and let me push that through. So yeah, so that's kind of what we will tend to see as far as I'm aware. So yeah, what did yours in under rest, Paul, your ECG was looking okay?

Paul Warloski (23:01)

Yes, yes. Yeah, so that was good. You know, and then I had to do the first round, I had to do the stress test and the EKG and then one other test looking for, you know, structural heart issues and all of that was clean.

Paul Laursen (23:17)

It's interesting. There's, I mean, technology continues to go forward. This is one of the companies that we collaborate with. They're called Frontier. They make a heart rate monitor called the Frontier X2, which you can actually wear during exercise. And it just looks like a classic polo or a Garmin chest strap or whatever you use. But it's actually measuring real time ECG. So you can actually...

hook that up to your computer and see it while you exercise. You could be on the trainer and moving around. And just like Paul did where he did like in the clinic, he can do a stress test, what he's referring to. But you can do this yourself actually and get your own sort of data. So that's quite fascinating and interesting technology that's now come to the forefront. And you know.

Again, so you can really start to pinpoint some of these potential issues, share them with your doctor, because you can totally get every heartbeat actually measured in an ECG trace while you go and do a five -hour ride if you wanted. So that's how incredible the technology is there.

Marjaana Rakai (24:38)

That's cool. Is there other complications that like say somebody has an AFib and totally just ignores it? I can see that happen. If you get into a AFib during your ride and you get dizzy, of course you can get seriously hurt, pass out and hurt yourself. But down the line, is there like a higher risk of developing stroke or anything like that?

Paul Laursen (25:00)


You know, I think this one is so massive, Marjaana, that like, you kind of can't ignore this one. It's so catastrophic, right? Like it's like you are basically, if you had any intent and shifting into zone three, four and five, you just can't do that anymore, right? You got to, you look at, you just, the thread on slow Twitch that we started, you know, the guy had to limp home basically at zone one, two, the rest of the ride.

He just basically, he no longer had access to the cardiac output that he needed to do what his body, or his brain wanted him to do. He just, you can't wheel through it. It's just, anaerobic metabolism just won't do it. You need your aerobic metabolism. And if your heart isn't delivering the oxygenated blood at rapid rates that we need when we exercise.

Marjaana Rakai (25:37)

Mm -hmm.

So you can't wheel through. Okay.

Paul Warloski (25:50)


Marjaana Rakai (25:54)


Paul Laursen (26:04)

You're just gonna fully know about it and you're gonna feel awful, right? You're gonna feel lightheaded, you're gonna feel dizzy, you're gonna feel that flutter. You might even feel nauseous. I don't know, Paul, am I missing any symptoms that you possibly feel?

Paul Warloski (26:20)

No, those are all of them. And with both, I mean, VT can be a little bit, I described it as the surly older brother because it can be a little more serious, but sudden heart attacks are entirely possible on the bike, on the run. I mean, it can happen right there. So it's definitely, I trifled with it last summer because I thought it was just nerves or something. I don't know what I thought it was. I just ignored it.

but when I went into the first doctor, I maybe, I don't know if I've said this on the podcast, but he took a look at me and he looked at my data and it looked at me again. He said, I'm just glad you're not dead. And it's like, this is a little more serious than I thought it was. and, and that's, you know, it's a reality that I think, you know, we, we have to face and that kind of brings me to, you know, a question I remember.

taking on a new coaching client and he is in his 50s. And that was one of the questions he asked me. Do I need to be worried about AFib and what do you think?

Paul Laursen (27:34)

Well, I think it's not really like, I mean, the incidence as we spoke about is low across the general population. And it might be a little bit higher in athletes due to what we're sort of talking about here, males and age, but it's kind of...

You know, there is, you could get screened if there's any worry. There's, you know, the full level of screening that you're speaking about, Paul, is always a possibility. And if there's any concern, well, why not? It's never going to hurt to go get tested if you're concerned about this. But, you know, if you've led a generally fairly healthy life and you've exercised in various different sports.

then it's not something that I would go and recommend and do necessarily. But conversely, if you've, you know, maybe in the context where you've had admittedly an unhealthy life and there's any feelings of anxiety around the health of the heart, then to me it's, you know, in that context, probably prudent to go and get the same workout.

workup that you just, you did with your Dr. Paul.

Marjaana Rakai (29:02)

Does nutrition play in the role here?

Paul Laursen (29:06)

Well, that's what Phil and Naftone, who I alluded to before, and I believe can contribute. But it's, I mean, we're guessing, right? So, but I mean, I even, you know, I think to my own poor nutrition habits that I succumb to in my late teens, early twenties and thirties, and, you know, drinking, you know, two liter.

Coke a day at some points during there thinking I was doing the right thing because I was putting carbohydrates into my system to train harder. That's, yeah, I wasn't living a healthy life. So, and that's those moments, I think many of us have had those and those add up over the lifetime of a human. And I'm probably a f***ing f***

feeling the effects of some of my hip arthritis, that's probably contributed to that along the way, if I'm being honest. So we all have these moments and stuff in our life. And yeah, so I believe those can contribute to the development of these issues. In other words, there's likely both an environmental on top of a genetic.

predisposition to any of these sorts of things.

Marjaana Rakai (30:37)

What advice would you give to athletes who recently been diagnosed with AFib?

Paul Laursen (30:43)

Well, like Paul, I would definitely go and, you know, don't be a hero and really, you know, listen to the real effect and go and see your GP. And if the GP isn't really being helpful, go see another GP until you get the help and the assessment that you're after. I wouldn't dismiss it if you know intuitively that things aren't right, then go get the help that you need. And...

Paul Warloski (31:13)


Paul Laursen (31:14)

Yeah, I know.

Marjaana Rakai (31:14)

Yeah, I like, I could imagine somebody who is looking fit and healthy walking into your GP's office. Like, what are you doing here? You know, like I can see many doctors would just dismiss that.

Paul Laursen (31:25)

The phone.

Paul Warloski (31:26)

Thank you.

Paul Laursen (31:30)

Yeah, you got to get the right doctor, right? Like that's so key. And, you know, every doctor is unique, just like all of us humans are unique. So if, you know, use your own common sense, if you're not getting the information or the help that you feel you need to, then you need to move on to the next one. There's lots of doctors out there. And, yeah, I guess I just had another thought like this is I've been through this whole thing when I was with New Zealand Olympic program.

with one of the, maybe I won't say the name, but one of the elite female athletes who was, you know, she was at the time, I believe she was ranked number eight in the world in the ITUs. And so she had this and she had what so, cause we haven't talked about solutions, there's surgical solutions. What she had was something called a laser ablation where because the atrias were, you know, not basically,

the wires or the nerves in the atrias were not, they were moved the wrong way. So she wasn't getting the same sort of kick to her atrias to push that blood down. They had the laser ablation. So basically, as I understand it, the surgeon goes in there and carves new, with a laser, carves new pathways for the nerves through that atria so that everything kind of kicks through and starts working again. So.

And she successfully had the surgery kicked back and performed in the Olympics. So there are successful, she would have been in her early thirties at the time, but there are successful procedures that can occur for athletes that have these electro, cardio, electrical issues, heart issues. And you even look at, you know,

Dave Scott and Scott Tinley are under the knife right now as we speak. They're gonna get solutions for their aortic stenosis that they're going in for as well. So all of these things have the potential to be fixed. Don't be discouraged if you have these issues. You included Paul. And yeah, just keep pushing.

the conversation forward, the communication forward of your issues with your medical team and work towards a solution for yourself.

Paul Warloski (34:01)

Yeah, thank you. And I think that's where we're going. We're trying to decide the second round here, what's the best course? Do we do another ablation where they actually kind of go in through one of your arteries and come into your heart and they burn a spot? Do we get on some medication? I'm kind of low to get on medication, but if it works, it works. And, you know,

depending on what the side effects might be, or we just leave it and see what happens from that. So this was a complicated conversation to do our three takeaways here. And I'm gonna give it a shot. And if either one of you two wanna chime in afterwards, I would say number one, the AFib and heart issues that we've been talking about are serious. Get medical help, get.

get it to have your doctor run the tests. Be careful because this could be fatal. Number two, if you don't have heart issues,

It is more likely that a polarized kind of plan where you are doing a lot of slow volume and then shorter stints of hard kind of intensity might be a better option simply because there's less time that your heart is super stressed. And third, AFib and ventricular tachycardia and other heart issues.

kind of abnormalities shouldn't be something that stops you from exercising. You know, one of the things that we talk a lot about on this podcast and with Athletica is that, you know, the same principle of balanced holistic approach to training that you are taking care of your, of your good health.

Paul Laursen (36:04)

That's perfect, Paul. I couldn't add any more.

Paul Warloski (36:08)

All right, so that is all for this week. Keep in mind, if you suspect you have AFib or VT, you should see your doctor immediately. Thanks for listening and join us next week for the Athletes Compass podcast. You can help us by asking your training questions in the comments, liking and sharing the podcast, giving us five star reviews and engaging with us on social media for Marjaana Rakai and Dr. Paul Larson.

I'm Paul Wurlowski and this has been the Athletes Compass Podcast. Thanks for listening.

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