I've just joined the community & am interested if others have similar experience as I will cover here.
As an intro I was training for a charity cycle ride in Malawi 2 years ago and in summary developed symptoms that resulted in an emergency transfer from the GP to hospital whereupon I was diagnosed as having had at "some time a heart attack". I had none of the typical symptoms, hence it couldn't be identified as to when it had happened. This resulted in requiring a quadrupal heart bypass within a few days. Obviously I had to pull out from the charity challenge in Africa.
I'm actually not an avid cyclist but I did sign up for another charity ride with the charity again this year, to cover 300 miles over 6 days in Kenya. Much of it was at some altitude. This I completed within the last month and glad to say I had no issues relating to my heart.
However, I am of course taking medication including Beta Blockers, in my case Bisoprolol. And this leads to my question.
The route in Kenya was extremely hilly, and while I coped well with the distance etc (BTW I had trained extensively for months before the trip), as soon as I hit a hill, which were often steep and could be long, my legs almost immediately tired. No chest pain or particular breathlessness (aside from the level you'd expect!). This resulted in my having to take hills very slowly in the lowest gear and resulted often in my being the last to complete a section out of the 30 cyclists. As said I'm not an obsessive cyclist but try to support these charity rides on Mountain Bikes and duly train accordingly. And it is unusual that I'm "at the back". This was the first African ride post operation. Frankly I was and am totally bewildered why I couldn't cope at all with the hills.
I have though been reading that Beta Blockers can create this symptom if training hard, and the heart by way of bpm is being in effect limited. Some cycling forums have posts suggesting this with one or two guys suggesting that since being on Beta Blockers, hill climbing is a real challenge. I'll probably be taking a chat with my doctor, but I'd be interested in any experiences that others have had with extreme muscle fatique like this?
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Paddington3
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I had OHS last year for mechanical mitral valve replacement. I'm 52 and on 5mg Bisoprolol. I have done a few 5km parkruns. Towards the end of the run I feel so incredibly fatigued. I never experienced this tiredness before surgery and Bisoprolol. Seems Bisoprolol is a limitator.
I do a lot of cycling and the bisoprolol was lowering my heart rate to much as I was fit through the cycling anyway. So I agreed with the doctor to trial coming off them two years ago and it has been fine since, my heart rate resting is still low.
I can't say I have noticed the hill issue but tbh I'm never trying to speed up them anyway. I had the same as yourself a quad bypass
You are 59, had a quad bypass and are climbing up steep hills at altitude. Any one of those could be a reason for not being as active as in your 20's but collectively I think you have done incredibly well to do these challenges let alone finish them.
I will be interested to hear what your doctor says but I would imagine they would be astonished at your level of activity.
I’m sure the bisoprol doesn’t help but how trained on hills are you anyway? I was an avid club cyclist , great at pulling the train along and utterly shite at hills . After a trip to the Alps I did hit some form but I’ll never be comfortable on hills, it’s always going to be a chore due to my build /physiology. I had quadruple bypass in July 2023, rehabbed really well, was doing Parkrun but then found out why my left leg/knee was agony in the evenings .. needed a new hip 🤦🏼. Had that on 17th October and will be back in the saddle , upright , flat bars this week for rehab 👍🏻
And a couple of others 👍🏻. Cracking trip. Col de la Croux de Fer was incredible. Col d’Ornon .. the descents were crazy.. blew a rear down Alpe D’Huez, luckily as hit the bottom and it flattened out .. running repair , boot, got us home.
I'm 65 and a leisure cyclist who rides 15 miles or so at a time, several times a week, just for exercise. Since a 1 August 2024 MI and the acquisition of a stent I've been able to cycle further and faster than before it. This was predicted by the physiologist who carried out my cardio rehab assessment, who told me that as I'd previously been cycling with a blocked artery, it would likely be easier now.
I haven't however been prescribed anything to lower my heart rate, although I'm on a fairly conventional cocktail of lansoprazole, aspirin, atorvastatin and Ramipril. I can't say that I cycle at altitude at all, but have definitely noticed a difference since getting back on my bike again. (Just shy of one month after being discharged.)
I have exactly the same experience as you have. I could not run or cycle hills, while speed is not an issue. Resting heart rate is good, but I have noticed that I need longer to warm up. I have lowered the beta blocker dosage (under doctor supervision) and that seems to help. I had quad bypass 3 years again, but unfortunately have to keep taking some kind of beta blocker due to other issues.
Have a chat with your doctor or consultant. Good luck!
Yes, Beta blockers are designed to suppress/limit the heart (rate), to help protect it. So almost certainly, when you are climbing (even more so at altitude) your heart rate won't be able to get high enough to supply enough blood/oxygen to meet your body's needs. If you wore a heart rate monitor during the Kenya climbs, you could maybe check out what your HR reached. To sustain long, tough climbs at altitude you'd probably need a HR of at least 120/130s, possibly higher depending on your physiology, which is probably not achievable on Beta blockers? You could also perhaps check your HR again now when doing longish climbs? Finally, have you checked (recently) with your cardiologist to see whether you still need to keep taking Beta blockers, or whether (2 yrs on from your Op) you could now be weaned off safely?
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