For the level of exercise that you are doing, I believe that you have a normal heart rate on exertion.
I do not think that you need to worry about this,
This is putting stress on your heart, but it is not likely to increase your risk of heart attack or stroke, if you are otherwise fit and healthy !
You should certainly discuss this with your doctor during your next visit, but no need to be worried about it,
I have a couple of stones of 'muscles' that I would like to lose as well :)
You are over the average maximal heart rate for your age.
Do not keep doing this until your doctor has cleared you.
I am a double board certified clinical doctor.
At your age you need:
Keep your heart rate lower in the meantime.
Being overweight, female, and age 68 puts you in a group that is underdiagnosed in terms of heart problems.
Get cleared by your doc. You can't get cleared on the internet.
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