Question about heart rate

hotel4dogs

I normally have a low heart rate (45-50 bpm), probably because I swim a lot.
When I do the treadmill/bike/elliptical I have a hard time getting my HR above 100 or 110, my muscles can't take what's required to get above that.
Does this effect my calories burned, or can I still use the basic calculators based on age, sex, weight, distance, time etc. etc.?

AnnPT77

It's the work being done (in the physics sense) that is the main determinant of calories burned, not how hard your heart beats while you're doing it.

So, standard calculators/calculations should be as accurate for you as they are for anyone else (i.e., possibly not very ), assuming we're talking about calculators and not heart rate monitors or heart-rate-based fitness trackers.

If you have non-average heart rate response, the HR devices might well be less accurate for you (though having a resting rate of 45-50 isn't automatically unsual enough to make that a special problem).

Purely having a low resting heart rate (or even having high fitness) shouldn't prevent you getting your heart rate higher. If you work harder (higher resistance, speed, that sort of thing), your heart rate should increase. When you say that your muscles can't take it, I assume you're saying you're just not strong enough at those other exercises, or that there a medical problem or something . . . .

hotel4dogs

Thanks for your reply!
Yes, I do have a medical issue. I have an autoimmune muscle disease (polymyositis) in which my immune system attacks my muscles. If I break down muscle tissue, releasing enzymes into my blood, it causes flares of the disease. Because of it, I also can't do any eccentric exercise. And, I have to be very very careful how much I stress my muscles.
I swim 1-1/2 miles, 3 times a week. On 3 of the other days I do 20 minutes on the treadmill at 4 mph, 20 minutes on the recumbent bike at 20 mph, and 10 on the elliptical which is a killer. But my HR rarely gets above 100, and never above 110.
I used to LOVE to lift weights. Can't do weights at all any more

Leslierussell4134

How old are you? And do you take a medication for blood pressure ?

hotel4dogs

I'm 60. No, I don't take anything for blood pressure. My blood pressure is generally about 90/60.