Catch 22: HR and training at 68 after 20 yrs of desk?

Hi All,
Great conversations and info here that I really appreciate. I’m just starting out training, finished LV SSB1 week six and taking a new ftp test tomorrow. I am amazed that I am able to do this at all, which brings up my question about heart rates.

According to MAF I should exercise at 107 bpm (180-68-5 for sitting on ass for 20+). According to 220 minus age my max should be 158 and that puts zone 2 HR at ±110. Here is what I am not understanding: when I started exercising on a trainer, I couldn’t stay at that low a rate for any amount of time, like not even 2 minutes. So I ignored it because I felt fine and eventually in a couple of weeks was able to cycle for half an hour at 135 or so.

Now I can do 1.5 hours with an average rate of 139 on the bits that Chad has added in Brasstown. How on earth would I ever have been able to do this by exercising only at 110 bpm? Being old and sedentary my heart rte used to go that high cleaning the cat barf before my coffee. It would hit 135 while I was walking. Now my rate has gone as high as 180 and when I work in heart zones based on that rate I can talk and ride a long time in zone 2, around 140, without getting winded at all.

Some factors that come to mind:
When I was a kid I had a paper route for three years riding up and down hills with 40 pounds of paper over my head every day, heavier on Sunday
Until I was 45 I ran 2 to 3 miles every day. Then I had knee surgery and became sedentary. I also drank way too much beer and gained a bunch of weight ±50 lbs. The stress of my job and the lack of exercise gave me cortisol and high blood pressure. By the end of 2015 I would get tachycardia from almost any exercise. My doc put me on meds and tried to start me down the statin trail. So I had to alter a few things.

Since 2016 I have lost 45 pounds by changing diet, nothing much unusual, just consistency and making better choices. I also quit drinking alcohol–just didn’t feel good anymore so I stopped one day. After 2 years I no longer needed blood pressure meds, and I had an angiogram thingy done that showed I was lower risk for heart attack than they thought.

With all of that, the missing ingredient was exercise. So I bought an ebike on December 31 and rode it new years day. It was a blast so I bought some gear and kept riding. Then it was too cold and wet so I bought a trainer. That led me to the Tacx site with films, then I discovered Zwift and Wow! But I found that Zwift was too much–I could only last 10 or 15 minutes to begin. By the time I could ride for an entire course I was also getting recovery times from my watch of 59 hours. Then I discovered TrainerRoad, quit Zwift and started training and the experience has been genuinely excellent (one unexpected side effect of all this training is that I suddenly got a bad case of gas–gear acquisition syndrome–forcing me to buy a new bike and power meter, thanks guys).

So now I weigh 142 at 5’10" and Friday when I was stuck riding uphill in a headwind I hit 390 watts keeping form in saddle! I am not a powerhouse of any kind, my FTP is currently 93, so this amazed me and I will really be disappointed if I don’t better that on this next test. Might sound low, but I really think I was half-dead and the bicycle has saved my life. TrainerRoad gave me the confidence to hit it and not worry about whether I’m gonna be giving myself a heart attack. The confidence to go riding is exhilarating after years of sitting and staring at a screen.

But here’s the thing I wonder–how would I have made progress if I hadn’t ignored the max calcs in all of their forms? Following TrainerRoad immediately blew up any keeping in heart zones for me, but over time everything is getting more efficient.

I suppose what I am getting at is that it seems none of the HR calcs are designed for people who are badly deconditioned, and pretty useless if that is your situation. Am I missing something here? Am I killing myself by cheerily exercising up to 174 bpm? Even though I feel excellent after the workout and the recovery times are lower than 24 hours?

All of this is confusing and contradictory and makes me believe that there is an entire new frontier for training people like me. I am far less dead than I thought and those training recs for normally healthy people aren’t a great help. In any case, I’m really really curious about others experiences.


First up, just wanted to say that those are awesome improvements, both in your health, and your fitness.

The thing about maximum heart rates is that they vary significantly from person to person (even of the same age) - largely for reasons of genetics than fitness (or lack of). The maximum heart rate formulas are a reasonable prediction of the average of the population as a whole, but like most averages is actually made up of a broad spread of individual points, and is a poor predictor for any one individual. Half the population has a maximum heart rate higher than that predicted by the formula.

HR zones become much more useful once you start using YOUR personal maxHR, rather than the formula prediction.

TR sidesteps all of this by using power instead of heart rate. And that is what you should be using to guide your efforts.