EPOisDope

I understand that this whole post is a bit irrational, but I prefer to think of it as being "driven"! I'm a seasoned cyclist (currently 45 years old, 30 years of riding, 15 years of racing, racing ended in 2010) who had a serious "widowmaker" heart attack from a blood clot a few years ago, along with several pulmonary embolisms and DVTs throughout the past several years. Not surprisingly, my fitness has suffered. I still ride well over 10,000 miles a year, but anything at or above threshold level become a problem. VO2 efforts don't go particularly well, but hard anaerobic efforts of around a minute are even worse. They cause a good amount of tingling throughout my body when really digging deep, along with lightheadedness. I believe that might be coming from hypoxia, although I'm not 100% certain about that. I think I've accepted that 1-minute max efforts are a thing of the past, but I'm still a time trialist at heart (no pun intended), and would like to improve my FTP. What I'm trying to figure out is how important the heart itself is for threshold power, and whether the heart itself is now what determines my "ceiling", or if it is more an age thing that is holding me back. The heart recovered very well considering the severity of the heart attack, but the efficiency of the heart, something called ejection fraction, is still much lower than normal at 45% (normal is about 60%, was 30% just after the heart attack). The other clots have caused a slight amount of lung / vein damage, but I think those are making a very slight difference. So, if my FTP is 80-85% of what it was back at my peak, is that about all I can ask?


Thanks,

Dave

Carbonfiberboy 

Has your HR at a particular power number changed, and if so, what percent up or down? Has your hematocrit changed? When you use a pulse oximeter during your hard efforts, what does it get down to? In any case, I think you're doing really well at that percentage. Seems to me unlikely to be able to raise FTP further.

If your LAD was blocked for some period of time, seems like you'd have some muscle damage. A heart with muscle damage just won't pump as much blood. You have the numbers for that, though increasing HR by 25% would make up for the 25% lower fraction. Blood volume per unit time is what makes power if we take muscle conditioning and lungs out of the question. I think that's that.

EPOisDope

My heart rate has remained quite similar to what is was before. My hematocrit / hemoglobin levels are also about the same as they have always been - middle of the normal range, although I've never had it tested during or immediately after exercise. My resting heart rate is higher than it used to be (was upper-30s, now mid-40s), and my max HR is now 170. Threshold HR is 150-155. I always had a relatively low heart rate, so other than a higher resting heart rate, that's about where it should be.

I've never used a pulse oximeter during a ride. I didn't know that they were so readily available! That might be a very useful tool for me considering what I'm fighting. That would answer the question as to whether the strong tingling sensations I get during 1-minute intervals is in fact hypoxia. I can't believe that, as involved as I am in this sport, I never heard people discuss using one!

There was a lot of damage around the LAD. The way my heart compensated was to significantly enlarge the left ventricle. So, instead of having a normal "athletic" heart, I now have a VERY large and inefficient left ventricle. I went from a modern V6 turbo to a 60's V8 - doesn't make as much power, and burns a whole lot more gas in the process!

Dave

Carbonfiberboy 

Well, there ya go. Smaller ejection fraction, same HR = less blood moving through your muscles. Same hematocrit = blood's not carrying more oxygen, which would be helpful. One thing you could do, which I've done, is to donate plasma. For unknow reasons, causes EPO release and thus raises hematocrit. Endogenous though, so you're not drugging.

zacster

You shouldn't be asking this question on a forum. Find a sports physician or cardiologist to answer this.

79pmooney

Heart attacks can and do happen in very fit people from plaque detaching from artery walls and blocking blood supply to the heart and hence oxygen. Plaque is related to diet and can happen in very fit athletes. (Years ago, the runner Jim Fixx advocated running as an activity that allowed you to eat anything with impunity. He died of a widowmaker as a marathon-fit athlete.)

Carbonfiberboy 

Plague is medically knows as coronary calcium. So there's a coronary calcium score (CAC), a number calculated from a CT scan of the heart. A high CAC score is heritable. If there is an association between diet and CAC score, it is at this point unknown. There is a moderately strong positive association between high CAC score and being an endurance athlete. Most people don't realize this because CT scans are expensive and insurance won't pay for them without good reason. "Good reason" is a heart attack or some other coronary issue.

I have a high calcium score and have been a vegetarian since I was 21. It is known that neither statins nor diet will reduce a high calcium score, though it's possible that statins can help stabilize that coronary calcium. There's still debate about that - no one knows for sure how statins help to prevent heart attacks, except that researchers are fairly sure now that reducing cholesterol is a side effect and is thus correlated with the reduction in heart attacks but not causative of that reduction.

OTOH, a high calcium score isn't all that bad if one got it because of being an endurance athlete. Our calcium deposits are more solidly attached and have a different composition w/r to the coronary calcium of non-athletes.

https://www.acc.org/latest-in-cardio...ular-mortality
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4750794/
https://www.ahajournals.org/doi/full...aha.117.028750
and many other similar out there.

genejockey 

Jim Fixx also had a father who died at 43 from a SECOND heart attack, having had his first at 35, and Fixx's coronary arteries were heavily occluded with arteriosclerosis. He caught a bad roll of the genetic dice. Plaque is probably more closely related to your choice of grandparents than your diet, unless you're eating sticks of butter.

EPOisDope

In this particular case, my heart attack was caused by a blood clot. I have a bad history of blood clots, even when on blood thinners, including several pulmonary embolisms, several DVTs, a couple of minor strokes, etc. A heart catheterization took place a couple of years ago when they suspected additional heart issues, and the results were very good - no atherosclerosis. "Squeaky clean" was the official diagnosis! I unfortunately don't know the cause of the blood clots though, even after taking MANY blood tests (Factor V Leiden, Antiphospholipid antibodies, etc) to determine it. I have had a couple of serious car vs bike incidents, so I'm thinking that the trauma from those might have caused a narrowing of blood vessels somewhere, but that's just pure speculation at this point.


I also understand that this is a question for a cardiologist, but they, or at least those that I have been involved with, don't seem to have a lot of knowledge about exercise beyond walking. Most of their clientele isn't aiming to win a time trial! It seems that, since my heart muscle itself is quite damaged, it has enlarged to compensate, but I'm just trying to figure out if the heart itself is my current limiting factor, or if it is a combination of other things. The advice that Carbonfiberboy gave was very good - get a pulse oximeter. I ordered one and am awaiting its arrival. That might answer a lot of questions I've had.


Dave

Lemond1985

Interesting discussion. I had never even heard of pulse oximeters, but the $20 price tag sure looks intriguing. I'm assuming you put your finger in that thing, correct?

As a person who rides a lot in desert-like conditions, I wonder if excessive blood clotting might be related to hydration levels, as in not drinking enough water to replace perspiration.

Carbonfiberboy 

Yes, you just stick your finger in it. It has a tiny battery which lasts a very long time. It's an important Covid tool. The first sign that maybe one needs to dial 911 is a reading of 92 or less. https://www.houstonmethodist.org/blo...id-19-at-home/

93% is the reading when the kidneys start pumping out EPO, good idea. I've tried on my rollers, but haven't been able to get it down below 97. Need more power, I think. I did get it down there nicely doing jumping jacks at 10,000'.

Blood clotting is a risk associated with Afib, and a deadly one. Dehydration does raise the risk if your blood gets really thick.

I should have mentioned re my CAC score, that my older brother had a triple bypass at about 55. My mom had some heart issues too, but it was her osteoporosis which really did her in, early 90s though. I inherited that, too. But for me, so far, so good. My long-range plan is to keep on keeping on.

genejockey 

The last sentence there tells you what you need. Not more power. Less air.

Flip Flop Rider

it is essential

Richard Cranium

No, I would wonder why no heath professionals have warned you of ischemia resulting during hard exercise efforts. You may doing more harm than good.

My experience would suggest you should consider the risk/benefit ratio of any exercise levels. Like yourself, I have health issues that in theory should preclude exercising at high intensity - and like yourself I don't always ride with common sense as a guide.

EPOisDope

I can't argue that. Another element of the breathing issues could be some form of asthma. A couple of weeks ago I foolishly did an FTP test, which resulted in a bit of difficulty breathing towards the end of the hour, which, of course, I pushed through, and didn't go away completely when I was done. It wasn't severe - slight amount of chest tightness when I was just sitting around, but fairly significant during exercise. I was pretty convinced that it was another pulmonary embolism when it didn't clear after 3 days, and it felt very similar to previous PEs, so I decided to get it checked. According to a ct scan of the chest, there was no clot. Also no sign of heart damage, at least based on troponin levels and comparing an EKG to one taken a year ago. I asked my primary doctor for a prescription of Albuterol to see if some of this was more of a bronchospasm. So far the breathing seems a bit better with the inhaler, but like you said, I'm basically just playing with fire. I do have a disturbingly lengthy EKG interpretation, including left atrial enlargement, conduction delay, etc. Pushing this hard is just pointless, unless maybe USA cycling comes up with a new "Heart Attack Hero" category. I'm guessing that their legal team might have something to say about that! My fitness is way better than it should be given all of this, so I should really just be grateful for that instead of trying to put Filippo Ganna in his place.


Dave

Carbonfiberboy 

Just curious . . .what sort of conduction delay? I have a partial left bundle branch block. Doesn't seem to do any harm other than probably lower my heart's efficiency a bit. The doc said don't worry about it, so I don't. Left atrial enlargement, I think, is not good. But yeah, pushing too much is probably not the best idea. I'm in that same mood.

This winter, my project is simply to be able to ride my resistance rollers at 75% of last year's FTP for 2 hours steady without heart rate drift. I'm up to 90' now. IOW I'm trying to maximize my aerobic ability, which should cut down on my need for anaerobic work, which will lessen the load on my heart at the same power. I think. Today I did that 90' at 80% of LTHR or 73% of MHR, breathing very easily. That's what I'm looking for. Low end is really slow to train, high end trains quite quickly. I have to concentrate so hard on the details of pedaling and holding the same power and staying meditative and staying on the rollers that it's really not boring at all. I'm trying to work up to 8 hours a week of that one specific exercise. Then I'll think about what to add, probably some longish 105% intervals.

My hub power meter was new to me this past July. I'm really enjoying it, another interesting toy.

EPOisDope

Mine is defined as "RSR' OR QR PATTERN IN V1 SUGGESTS RIGHT VENTRICULAR CONDUCTION DELAY". The heartbeats are somewhat inconsistent when examined on an EKG, but are shockingly consistent when I wear a heart rate monitor. I don't normally wear a heart rate monitor when riding (I probably should though), but when I do, I almost never find any irregularities, other than my heart rate is always a lot lower than anyone else I know. Resting HR these days is up to the low 40s, LT HR is 150 and Max is 170.

Your training philosophy sounds very similar to mine, in that I'm fearful of LT or above. I do a TON of tempo riding and a fair amount of SST training. For a healthy person, spending a lot of time in L3 wouldn't accomplish much, and might be deemed as counter-productive since it doesn't quite stress the body enough like a good SST / threshold session would, and also doesn't allow the body to recover, but I normally do 2 - 4 hours of "hard tempo" because my heart doesn't seem very willing to go above that. L3 for a few hours definitely hurts! L5 / L6 efforts were never fun even in my racing days, but even less fun when you have arrhythmias when trying to fall asleep that night. I DO think that the extended L3 efforts have really helped improve things such as lactate buffering. Because of that, as you said, I don't HAVE to do as many VO2+ efforts on my rides, and I can recover from a climb pretty quickly. I WISH the heart could handle L4+, but it's simply too much stress on a damaged heart.

I have a hard enough time doing recovery rides on rollers. I'd surely be on the floor if I tried to do a 2-hour tempo / SST ride on them!

Carbonfiberboy 

75% of FTP should be relatively slow easy breathing, max HR for you would probably be ~120 before you go over AeT and start breathing faster. Faster is easier on rollers.
I rode my guts out once a week for years. That was a lot of fun, but maybe there were costs.

ARider2

I would suggest you find a cardiologist who has a practice that specializes in treating elite athletes. Then have a stress test performed which includes an echocardiogram before and after the stress test. The stress test will show how your heart is performing as the heart rate increases during the workout, and how long it takes to recover after the workout, and the echo will allow the doctor to see how the valves function. Have you had your cardiologist perform a stress test?

EPOisDope

I have had a couple of stress tests - one done on a treadmill, where I proved that cyclists are indeed the most awkward runners known to man, and last year I had a chemical stress test because my heart was deemed to be too damaged to perform one on a treadmill. One thing I've learned is to not trust all medical tests, as the echocardiogram that prompted last year's chemical stress test showed an ejection fraction of 28%, and a catheterization done right afterwards estimated it at 20%. I thought my days were numbered, but the final test, taken a couple of weeks later, was an MRI, which then showed about a 45% ejection fraction, and they basically said "oops" about the other tests being invalid! They apparently either used the wrong contrast or not enough contrast in those other tests. Anyway, the good news is that, while there is left atrial enlargement, I believe the valves themselves are OK. About a month or two ago I was having pretty bad breathing issues, so I got checked out to see if it was another pulmonary embolism. Luckily, this time around no clots were found. Since nothing abnormal showed up on the CT scan of my chest, and none of the blood tests came back with anything conclusive (troponin included), and the EKG came back without anything "new", I asked my doctor for a prescription for an inhaler. That really seems to have helped! I don't have a big enough sample size yet to say conclusively that it was asthma causing the "pins and needles", but even on today's ride, I did a couple of pretty solid efforts that would have previously caused me to almost pass out, but now I only have a "slight" pins and needles sensation, or none at all, when above 160 BPM. Goes to show that you should always start with the simple things!


All of that being said, what I'm trying to determine is if my heart is capable of doing 5-minute VO2Max efforts that are about 15% higher than my FTP, does that mean that the heart is not solely what is holding me back from improving my FTP? If we just push aside that whole "risk of dying" thing and pretend that no additional heart damage would occur, would I be still be able to improve my FTP / VO2Max? What gets "trained" in order to improve a healthy person's VO2 / FTP? Normally that would be a stronger heart, increased lung capacity, lactate buffering, more efficient muscles, etc. Assuming that I can't improve the damaged heart or slightly scarred lungs, what other things CAN still be improved to lift my FTP a bit higher?

Carbonfiberboy 

Aerobic exercise has been shown to raise FTP. 8-10 hours/week of aerobic exercise should help. "Aerobic" as used here means not anaerobic, which means keeping effort below the point at which breathing rate increases, known as AeT or VT1. Google. By HR, this is somewhere around 85% of LTHR at ~90 cadence. Breathing rate is probably more accurate, though even that is a bit sloppy. Below that anyway, not right at it, but a little below, which makes the sloppiness not so important. 2 hours of that without HR drift is the gold standard, which may take while to accomplish, depending on training state. This takes a lot more time than high end training for the same result in FTP, but it benefits more than just FTP. If one has lots of time, one can do this as much as one has time for. Outdoors, it's important to gear down for the hills to try to keep the effort down.

90 cadence at low effort doesn't do much for the legs, though every day will tire them out for sure. One can push the legs harder by gearing up. Power will go up for the same breathing and HR, so power isn't as good a metric for staying aerobic.

C_Heath

Im 48, if I go hard, the tip of my nose starts tingling. If I don't let up, it flows through my nose and into my face. When that starts I let up. I've never carried it past that, I just shut the fire down. If I get dropped so be it.

BikeLite

lol