I have always used a Heart Rate Monitor during all sessions, I know my max HR and my threshold HR. I have always been able to use my threshold HR to eg know when I have reached my limit during intervals.
Now that I am on medication for my AF, it works like a limiter on my HR and so I now do intervals where my HR only rises slightly in comparison to prior to my AF. I no longer know what my max HR is or my threshold, how am I supposed to conduct any type of session in line with HR when my HR is now not really aligned with the sessions?
I was diagnosed with AFib about 18 months ago. Just like you experience HR is no longer in line with previous experience. In my case, currently on bisoprolol (beta blocker), hr is usually 10-15 beats lower for the same power. This means that in z2 heart rate is considerably lower. For me this is no big deal as the effort is still z2, it’s just that the scale has changed.
Higher intensities is trickier as I can feel held back. Usually I stay of my medication about 24h ahead of anaerobic intervals and use power as a guidance. I still feel somewhat limited above threshold, but not to bad.
In my case i was advised to take bisoprolol in case of AFib or similar conditions so I wasn’t prescribed it on a daily basis. This gives me some room to tailor my medication to the circumstances.
Edit: For higher intensities training to power and use the power/duration curve as a guidance for intensities. As heart rate is far to slow to respond, power is superior in this case.
HR is no longer reliable and I know using RPE or power is a guideline but it doesn’t always reflect what you see on an HRM even when HR is normal but thanks.
I have to take the medication daily, bisoprolol is also what I use, it keeps my HR way lower than my usual HR. My max HR is 180, so when working on intervals I take my highest interval level to 165 absolutel max. With this medication when I do intervals, RPE is certainly as expected but my heart rate rarely goes above 125 and it’s usually lower - and to add to it, it can be completely different, ie lower but never over 125. I’ll look at the power/duartion curve, thank you.
I’d rely on the power numbers regardless of heart rate. HR has been shown to be not as useful as using power because of its variability.
Add a medication that affects heart rate and it becomes even less useful and could become a limiter.
As a person who has used heart rate for training since the 80’s I still find it hard not to use heart rate as a training tool instead of power numbers.
Perhaps doing the same workout…ie a TR interval session…and comparing the power numbers which should be around the same as pre medication numbers…if the power numbers match or are very close then compare heart rate numbers to see how the med is affecting your heart rate and what the new numbers…then the new numbers become the norm.
What is important regarding heart rate and power is the more fit you become the lower your heart rate will be during periods in tempo/sweet spot/threshold and vo2max.
for instance I did a zone 2/endurance, 3/tempo ride yesterday and my heart rate during the 5 minute tempo portions remained in the low endurance zone despite the watts being in the high tempo zone…cardio fitness very strong…this also works in the higher power zones…you can go harder with less effort…
Power alone is an excellent option and used for training for a reason, add in RPE and while it won’t be as much data as having HR as well it’s more than sufficient to train well.
So basically your hr has dropped about 15 beats for the same effort which is in line with my experience. From what i understand the body is able to compensate for the lower hr to some extent. A higher preload and lower afterload are possible adaptions. These are positive effects of a lower blood pressure. There are possibly other effects at play also.
When I was in persistent AFIB (before an ablation) I was also on bissoprolol. My cardiologist advised me to use RPE and largely ignore my HR - which was all over the place when exercising.
No doubt the beta blocker worked as a rev limiter.
I feel very lucky my ablation so far is sticking and I am off drugs.
Thanks Jakob, RPE and power it is now. Glad your ablation has worked well for you, I’m on the waiting list for one but not ,likely to happen this year!
Lowering your HR will probably cause your muscules receive less oxigen/utilising lactate slower at the same given power you had.
I’d not fully rely on previous power numbers and try to feel your body during first 2-3 workouts at Threshold level or above. You probably might need to lower FTP or shorten intervals a bit (3x12 -to 4x9 etc.) to have same RPE you had before.
South West London here. If you have any UK specific Q’s feel free to DM me. Caveat - I am not a doctor or medical professional - but sounds like I may be a little ahead of you in the AF journey.
This is not necessarily the case. The body has two primary ways to mitigate a reduction in VO2max: increased stroke volume and increased oxygen extraction in the muscle cell. There’s slight risk of lower lactate removal ability so mlss may be somewhat lower. In my personal experience RPE seem to be lower if anything, but i assume this is a highly personal experience.
I’ve had a couple of ablations plus two PVI procedures with pretty limited success, so I’m currently on diltiazem and flecainide. The highest HR I’ve seen—even when I’m absolutely emptying the tank—is around 154.
I agree a power meter is probably the best way to go. I don’t have one on the bike though, so I’ve more or less given up trying to do proper high-intensity intervals outdoors. These days I do them almost entirely indoors on the trainer.
I think I have ±established my new max Heart rate, but there seems to be quite a discrepancy indoors and outdoors (outdoors higher). So even going by HR combined with RPE, I tend to overcook it by the end of outdoor sessions.
RPE does seem to work well for longer intervals and / or lower intensity rides.
As an aside - My racing HR is a far higher percentage of my max than I can sustain training.