No problem and happy belated birthday. The target HR of 143 must be from 80% of your MHR, correct? If so, when you want to train at this intensity, stay as close to this level as you can. Because this is high intensity, you probably won't be able to maintain it very long. If you haven't been active consistently over the last 6 months or so, I'd check with your doctor before exercising this hard. Alternatively, you could exercise within a range. For example, 60-80% of your MHR. For you, this would be 106-143. When you get tired, just slow down a bit.

If you'd like to exercise at a moderate intensity - 50-70% of your MHR, follow the guidelines below. I used these in research projects when I was a professor at the University of Houston. They are well-accepted. See your doctor first, if you are:

1. Male and over 45 (you are right at the cusp)
2. Have 2 or more of the following:
   • family history
   • current smoker
   • are hypertensive
   • have high cholesterol
   • are type II diabetic
   • are more than 30 pounds (~15 kgs) overweight
   • or have been sedentary (no exercise at all) for 6 months or more
3. Have heart or blood vessel disease or something else not listed here.

Ultimately, you are the best judge of what you can do. These are just recommendations. I would encourage you to visit your doctor before performing anything too strenous, particularly if you have any of the above.

If you do have any of the above and just don't want to see your doctor, go easy and build up slowly.


I hope this helps. If not, let me know.

Brian