Sage

Heart rate monitors are great if you're just starting out, but basically cardio is about getting your heart rate up and keeping it up for long periods of time. My fitness guru (who's the greatest teacher on the planet) back in college believed in the talk test- you know you're doing it right when you're exerting yourself hard enough that chatting is an effort, but not so much that you don't want to do it. So you want to be at the point where you can carry on a conversation, but just. I've seen plenty of other litature to back this up.

The main thing is being at a pace that you're comfortable with. Everyone's heart is different and will handle stress differently. If you want to reduce your HR, reduce your pace. Less effort on your part means less effort on your heart's part. Also, since you used to smoke your heart probably isn't as strong someone who never smoked, so it has to work a bit harder.

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