I'm trying to pay more attention to my heart rate. Though I've never had any coronary incident and have been asymptomatic a coronary artery base had a stent implanted. Long story how I arrived at that.

I'm 73, have been cycling seriously, for me, for three years. Averaged 40-60 mi per week, had a few 100 mi weeks, longest single ride 42 mi, etc.

Anyway, according to the rule of thumb, my max heart rate is 149 (220-age). My resting heart rate is 47-49. My question, does my fairy low resting heart rate alter any of the other heart rate zones such as, per FitBit which is very accurate, fad burn, cardio, peak, etc?

220-age has been debunked. It may have some application across a population but it's useless for individuals. You are better off finding your lactate threshold HR and basing your training levels from that.

See: https://www.trainingpeaks.com/blog/j...setting-zones/

Or find your actual HRmax, but that's quite painful.

Thanks, I understand there are better ways, but really my point was how, if at all, might an abnormally low resting rate have any affect on the thresholds of other heart rate zones.

There's the Karvonen approach that uses resting HR as a baseline. https://en.wikipedia.org/wiki/Heart_...arvonen_method

Thanks, interesting stuff. I've bookmarked it. The 220-age may not be "the" most accurate, but my cardiologist felt it was good enough for my personal situation as a conservative guideline. I'm a geezer, not an Olympic athlete.

That it a low resting HR. I would consult your cardiologist. Are you on any cardio or BP meds?

How high can you get your HR? How fast does it recover? I would be more interested in this than an absolute number.

If you want to increase your fitness, do interval training and wear a monitor.

If you just want to ride for health rather than train for a race, forgo the monitor and just use your respiratory rate. I heart once if you cannot carry on a conversation, your HR is too high.

Besides that, with cycling one day you ride like an animal, the next you not sure you'll make it back!! LOL

Generally speaking, a low resting hr is from a well conditioned cardio system. However, it sounds like you don't know what your resting HR was before you got into cycling (correct me if I got that wrong). Some people have low resting heart rates (and low blood pressure) and it's a problem, so it's kind of dependent on the individual.

On the 220-age formula being debunked, this is an excellent article that explains why it has been debunked.

'Maximum' Heart Rate Theory Is Challenged - The New York Times

Long article, but here's one excerpt:

The zone breakpoints have to do with your body's metabolism of energy substrates, mostly fat and carbs and thus production of lactate. These breakpoints have nothing to do with your resting HR. HR isn't really all that great a way to determine your breakpoints in any case. Your breathing is a better way. In a 5 zone system, the breakpoint between zones 2 and 3 is VT1. The breakpoint between 4 and 5 is VT2. 1-2 is arbitrary as is 3-4. See:
https://www.acefitness.org/blog/1165...ng-vt1-and-vt2

I use breathing to determine my zonal HR breakpoints, which do vary a little with training. Once I have those, I watch HR but still pay attention to breathing. I ignore max HR, but I do occasionally test for lactate threshold HR.

I'm under the care of a cardiologist. He did put me on BP meds, but it's an ace inhibitor so shouldn't affect my heart rate much, at most 2-3 bpm. I don't know what my resting rate was say 4 years ago. I was a runner back in the old days, not sure if that makes any difference now. I can get my heart rate up to 130, but it is work. I don't ever feel out of breath and my heart rate returns fairly quickly. I believe I read in the material that it should drop 12 bpm in the first minute after you stop the exercise and mine does. I road with a MIO link HM for the past two years, I'll have to go back through my Strava records to see what the maxes were. I never calibrated the MIO though against anything. I wear a Fitbit now day-to-day and it is accurate. I've checked it numerous times againt a monitor with chest leads while exercising. The only difference is the monitor with leads seem to be more responsive to change whereas the Fitbit takes a couple of seconds to respond.

Edit: if this works, here's a typical 24 mi ride I do regularly before my accident last fall. Per the MIO Link my HR was between 110-120 most of the time.

My resting HR goes as low as 44 sometimes. 46-48 is totally normal for a cyclist. I have a riding buddy who's much better conditioned and talented than am I whose resting HR is 40. He has a note to that effect on his RiderID, not a bad idea. I suppose I have "low blood pressure" for the American population of my age, usually 106/68, but that's actually what the medical community would like all of us to have.

Your TRIMP of 88/hour is quite normal, so my guess would be that your zones are somewhere in the ballpark. My Strava TRIMPs run between 75 and 110 per hour, depending on my level of conditioning. The better shape I'm in, the longer I can hold high HRs. On a killer 3 hour ride when I'm in good shape, my average HR will be as high as 92% of lactate threshold HR (LTHR). Your watts/kg is also normal for average riders of your age.

If it's OK with your cardiologist, you should push your effort and HR up into the panting zone on climbs of less than 10 minutes, so maybe ~142, maybe higher. That's how you get faster. That'll also bring up your Strava average watts/kg. But do ask that direct question of the doctor.

You should push your median cadence up. 85 would be a good target. A higher cadence will increase your HR slightly (no big deal) but will also increase your endurance (big deal.) Running a consistently higher cadence might temporarily drop your average watts a little, but that'll come back up as you adapt.

Carbon; thanks for the feedback. My resting heart rate is consistently 49 of late. My cardiologist is aware and attributes it to my overall condition (with the exception of my coronary artery issue ). This same evaluation by staff in the U.P. hospital where my leg surgery took place, determined they could go ahead with the repair even though a nuclear stress test suggested and abnormality. They stronly suggested a follow-up upon returning home. End result, more tests and ultimately a stent in one artery.

My recovery re: my leg is pretty much complete. Now, I'm just trying to get back into the swing of things. I'd been entertaining a bike change to a gravel bike w/dropped bars. Our bikes, my hybrid, is still up in the U.P. We are going up over Easter to bring them back. Mine will go to my grandson. I've been using a modified Schwinn (to a road bike) on a fluid trainer. Going well, today averaged about 14 mph for 30 min.

I will reiterate please be careful with your history you may have underlying issues that have not been fully revealed. Also keep in mind gravel riding is much different exercise and can be much harder on the joints then road cycling. I strongly recommend consulting your Dr about repeating the stress test. I would not put much stock in training advice from people who may be much younger than you and in much better condition.

Unless you're basing your zones off %HRR (as caloso mentioned) it has no effect whatsoever.

Keep in mind that cardiologists are not exercise specialists, so he's not thinking about a useful way to understand your zone breakdown while you ride, he's thinking about you not passing out. It's good that you've cleared this with your cardiologist, but I don't think (s)he answered your question.

I've been cleared for whatever I wish, but I never specifically asked about any affect on my zones. I will next appt. out of curiosity, but that's not for 5 more months at a follow-up.

Not really. It would affect your zones if they're based on Heart Rate Reserve, which is defined as the range from your resting HR to your max HR. In that case you should really know your true max HR, because with somebody who has a really low resting HR, their max HR is probably lower than average also. In that case using 220-age could throw things off.

IMHO the threshold-based zones (using Friel's 30-min test to determine threshold HR) are the most useful. Partly because people are more likely to end up with accurate zones based on threshold HR rather than trying to determine max HR. But also because threshold-based HR zones will scale with fitness. As you get more fit, your threshold HR will tend to go up (to a certain point, there will still be a ceiling). So having HR zones based on your current fitness level is more useful (just like using FTP to determine training zones with power meters).