I'm in my mid-40s and I do cardio 3x weekly, and during my sessions, it's basically HIIT training. I try to keep my HR above 150 during my sessions, but it peaks in the low 180s intermittently.
Is this okay? My doctor noted potential concerns with getting my HR up that high, but it could be fine, she wasn't sure. I don't get any dizziness or anything (generally that happens if I sustain a heart rate above 185 for a bit). I'm not staying at 180 bpm, that's just the peak, I'm targeting an average HR of around 150-155 for my workouts.
In a 60 minute workout, I'll probably spend 10-15 minutes with my HR between 166 and 182 range.
Not sure if I should scale it down a bit or take it easier, or if this is fine.
It sounds like you're doing the right stuff. The only other advice I can give is to work on stress and try not to keep it inside. Also keep track of blood pressure. I brought all of this stuff up because I didn't pay attention to my stress and paid the price last year when I had a heart attack. All of my numbers were good, but I keep my stress inside and have a lot of anxiety and it caught up to me. If you have any chest pain even if it seems minor, talk to your doctor about it and if you have any kind of indigestion issues that are persistent also talk to your doctor. We're all different and my issues may not be yours, but if something isn't feeling right talk to your doctor.