Recently, a regular on our local group rides past away from a heart attack that he suffered during the ride. He was a very fit middle-aged man and I had just gotten to know him, it shocked me to the core. Anecdotally, this is the 4th endurance athlete I know of locally that suffered a heart attack and the 3rd to pass away from one.
Someone in our local group shared this video from Dr. James O’Keefe, a cardiologist with a personal background in endurance sports. You can see the video here. Granted the video is with reference to marathons, but I think it can apply to any endurance sport. In summary, he suggest that you should limit strenuous exercise to no more than 7 hours a week, especially if you’re over 40 years old. Given that his basis of non-strenuous exercise is walking, I would assume strenuous is anything over an endurance zone for cycling. In another video he suggests that shorter HIIT workouts are more heart-safe than long workouts at relatively high intensity, I would assume that would be something like sweet-spot or FTP.
I’ve heard about high-level endurance athletes having heart attacks and heart problems, but I guess I never realized that it also affects your average amateur cyclist too; it was like a gut punch. 7 hours a week is basically two 50 mile group rides, so does that just go out the window in light of this information? Do I go back down to low-volume training?
I plan on pushing my doctor to let me see a cardiologist, but has the effect of endurance training ever factored into your training plan and fitness goals? Prior to the recent events, I would have never thought I might be damaging my heart with endurance training.
EDIT: I should mention that I have a family history of heart problems. I started cycling a few years ago for heart health, but it has since morphed into a desire for a high level of cycling fitness.
I’m sorry to hear about the loss of a riding pal, that would be hard to deal with, especially knowing it could happen to anyone of you or us.
With regards to myself, I was experiencing excruciating headaches after short bouts of high intensity or maximum efforts. It prompted me to see a cardiologist and undergo a stress test. Thankfully I checked out as normal, but I do think it’s something we should all do periodically.
In terms of how you let this make an affect on your training is totally up to you, but I would encourage you get cleared by a doctor for peace of mind.
There are other related and useful threads on Slowtwitch.
TLDR: probably worth getting stress tests and calcium scores done once over 35 or 40 or something. Fitness can be very high with substantial high-risk blockages. The only way to find out is have a heart attack or get checked with calcium score… I believe. Don’t quote me. I’m not an MD. Just a lowly sport physiologist approaching age 35 and who is getting some heart scanning done this summer
I’m sorry to hear about the loss of your riding mate, one of the unpleasant aspects of middle-agedness is that you are confronted with death and your own health.
I’d be cautious jumping to conclusions, though, because perception bias could be a factor here: I reckon that many of your friends and acquaintances are cyclists and athletic. So if someone has a heart attack, they are likelier to also be a cyclist.
I’m not an MD, but as far as I understand aerobic exercise is, on average, good for health in general and the cardiovascular system in particular. Athletes also tend to eat healthier, and I reckon the risk of suffering a heart attack is actually lower as compared with the general population. I reckon that statistically speaking, overuse injuries (joints, etc.) are much more significant. Perhaps there is a tipping point if you do tons of sports, but you’d likely have to do a lot of exercise. Likely, it’d also depend on the type of rides that you do — a 4-hour Z2 ride will be different than a 3-hour 90 % effort.
Nevertheless, if there is a history of heart disease in your family, I’d get regular checkups and ask an MD, preferably one with a background in sports. Individual risk is different from statistical averages, you are not a statistic.
I’m not sure the “everybody dies” response is particularly tasteful here. OP, I’m really sorry to hear that- I just had a friend who got into a (fortunately non-fatal) accident and the suddenness has really shaken me as well, so I can’t imagine what that must feel like.
I also think there’s space for enjoying cycling while being informed about the potential for risk and making adjustments as you feel comfortable, and that would start with a discussion with a specialist (preferably one that has experience with endurance athletes), along with the appropriate tests. No downside there
Well it’s true. And so ask yourself what and who are important. Protect that which needs protecting. And other considerations that transcend this forum. And live everyday as if it’s your last. Sounds cliche, so flame away. Ciao.
Life is a challenge and if we listen to everything out there about what may happen……we could be frozen to inaction. There is always someone out there saying something negative about positive actions. We can do too much of anything. I wouldn’t change anything except if you notice an issue get it checked. See a doctor if you are concerned.
To give you the other side of things I was in my mid 50s and doctor told me I was high risk for a heart attack. Too much weight, etc. So I dropped 30 pounds in the next four months and started to cycle every second day. Next appointment to the doctor I am asked what happened? Am I sick? Not well? I said you told me to drop weight so I did. So for roughly the last 5 years I have continued to cycle. Cholesterol counts went to next to nothing. My eyesight improved? Don’t need glasses to drive….only had them since I was 18. My chronic disease, crohns has improved as well.
Cycling led me to change many items in what I was doing and how I live. I now have more energy. Aging issues as I am now 61 seem to not be as bad for me as my friends. In effect I have a history of being sick most of my life. I now feel great. All this came from starting to cycle. No idea how long it will last but I am enjoying myself and will continue to do so.
There are always two sides to every issue. Balance is the key.
Op sorry to hear that. Your response to question what you’re doing is normal.
Having a high level of fitness substantially improves my everyday quality of life. I would not consider training less to add years to the end of my lifespan. As far as heart issues are concerned, endurance exercise (and all exercise) increases heart mass as well as other factors related to the heart. There may be some relationship btw that and risk of heart attack.
This reminds me of when people tell me some story about how they know or heard of someone who was hit by a car and died / became a paraplegic. They say it as if I should take my road cycling and go to spin class at the gym instead.
Anecdotal evidence isn’t a good metric to use to make decisions. I do not believe there exists any statistical evidence that endurance exercise (above some hours per week) is associated with increased risk of heart issues.
However, I wouldn’t be surprised pro cyclists (or any real pro level athletes) have some issues later in life (they train 30-40hpw and restrict diet - abuse their bodies pretty hard).
Last year I got “Occam’s COVID” (Had severe shortness of breath symptoms but tests came back negative, which put me through a bunch of tests for things like pulmonary embolism etc. until my wife got the same thing) Anyways they discovered I had a borderline large aortic dilation of 44mm. I got tested for all kinds of genetic factors and they’ve come back clean and since then I’ve had it monitored every 4 months or so and there is no growth. The science is still very immature with regards to athletes, but it looks like 18+ years of pretty intense aerobic exercise has increased the size of my aorta. But nobody really knows if endurance athletes have any negative long term effects of this. Studies are just starting to take shape at this time.
The main thing I took away from this is that medical science is pretty good at understanding the heart for most people, but endurance athletes are significant outliers. Still, seeing a doctor once you start getting into the “masters” category is a pretty wise idea to see if there is anything noteworthy that you should be concerned about.
Sorry to hear that OP, must be tough to have a friend and fellow rider being taken away.
I’ve read through the slowtwitch thread that @Dr_Alex_Harrison linked, pretty scary stuff in there. Key takeaway for me is that:
A. Being fit, even very fit is no guarantee to be low risk
B. Possibly very bad outcomes and surprises are preventable if we take even small symptoms seriously and take appropriate preventive / diagnostic action
C. There is no rule of thumb or general conditions to rely on. When in doubt, talk to your cardiologist
I think the important thing to understand here is that there are two different underlying physiological causes going on here. The two populations are (most likely) physiologically going to have two different reasons as to why they might have a heart attack, or cardiac arrest.
overweight, high cholesterol, sedentary, metabolic syndrome etc.
very fit, endurance athlete who exercises 10+ hours/week over many many years
The first population is more likely to experience a myocardial infarction, meaning the heart muscle becomes starved of blood supply and oxygen due to a blockage in one of the major arteries supplying the heart. The blockage is due to a build of cholesterol to put it simply. This might be due to lifestyle, genetics or a combination of the two. The portion of the heart muscle supplied by the said artery can end up being without blood supply for long enough for the muscle cells to die, leaving scarring and weakness in the heart wall, and death if the area affected is large enough.
The second population is more likely to have heart muscle changes due to exercise. When we exercise, the heart undergoes growth and hypertrophy just like any other muscle tissue in the body. This is a positive thing, as the heart is able to more efficiently pump a larger volume of blood per beat. This is why we see heart rate lowering in athletes.
In endurance athletes who exercise - arguably - excessively and over many years, this growth and hypertrophy of the heart muscle can cause some negative effects - the heart can stiffen, the volume within the ventricles themselves can decrease due to the increased muscle tissue, and this can result in a few different issues. One, a type of ‘heart failure’ where the heart is unable to effectively pump enough blood to the body to meet the demands. And two, electrical conduction issues within the heart due to the altered size and mechanics. This second issue is the more common reason to see sudden cardiac death in endurance athletes. Essentially the heart rhythm can change suddenly causing the ventricles to contract wildly (too fast, out of rhythm), the heart is unable to pump blood effectively, and the person will have a cardiac arrest.
Of course I am generalising hugely here and I am not saying that this is what happens in every case, as every person is different and is going to have different risk factors for heart issues - genetics/family history and lifestyle to name a few. Just hoping to help with some understanding as to the underlying reasons why these things can happen. Definitely not giving advice on what to do or not to do. Of course checking in with your GP and cardiologist if need be is always a good idea if you’re concerned.
To qualify my statements with some credentials, I’m an almost MD (final year med school) and a physiotherapist who has worked in sport for many years. Hope this helps.
Sorry to hear about your friend. It makes me feel very lucky. I had a heart attack (myocardial infarction) during a bike ride almost 4 years ago, aged 47. I think I had several on the one ride and mistakenly assumed I had heartburn, until the final episode after cycling up a long hill when the chest pain was so bad I couldn’t turn the pedals and called my wife to come and collect me. I then had another one when I got home, which floored me in excruciating pain for a good minute or 2. Even after that I tried to play it down as heartburn and wouldn’t let my wife call 999, after all I couldn’t be having a heart attack, by then I’d been cycling 3-5 times a week for 11 years and had the fitness of a 21 year old! It could only be heartburn - wrong! I even attended an out of hours clinic at my local hospital that night and was not even given an ECG (EKG) and sent home and told to take some antacids and get an ECG “just to be sure” (very bad! There was an enquiry after that!). I attended my GPs 2 days later, was given an ECG and sent straight to hospital while my GP called them up and started shouting at them, as I’d actually suffered a quite serious heart attack. I had a totally blocked LAD artery (the one which coined the term “The Widowmaker”) and ended up having it drilled through to clear the blockage and a stent fitted. I was EXTREMELY lucky as my blockage occurred gradually over time and my heart was able to compensate by back-filling and growing new capillaries across (this still amazes me!), until it no longer could cope with demand and gave me several early warnings. Had it blocked suddenly, I doubt I’d still be here.
So the message from me is DON’T IGNORE WARNING SIGNS especially during exercise and especially over the age of 40. Any chest pain, arm numbness, dizziness etc - stop exercising and get checked!
I truly believe that had I not been as fit as I was, this issue would have hit me a few years later and probably a cardiac arrest rather than a “warning” heart attack. So many middle aged men have “early warning” heart attacks and don’t even realise they have. In hindsight I had ‘angina’ type symptoms for a few years leading up to the event, such as heartburn and a feeling of rawness in my lungs after any hard rides, I don’t get any of that now my artery has been re-opened.
Ciao.