Tamara
A few very important points
1. The 220-age calculation is 100% useless. It is not based on any physiologic studies. Completely ignore it.

2. If you can talk while running you ARE aerobic no matter what your heart rate is. If you must breath between every word you are definitely anaerobic. (this has been extensively studied)

3. Professional VO2 and heart rate testing is the only reliable way to get your personal parameters. Your HR ranges are not going to be the same as someone elses, and will change as your fitness level changes. But it is totally unnecessary to do this unless you are racing to win.

4. HR training, while useful, is being over-emphasized in this thread. What are you shooting for? Prolonged aerobic runs? Just make sure you are able to talk the whole time.

5. It's strange, but anaerobic interval training, where you get to or near your max heart rate, (don't need to know what the number is, you can feel it.) is one of the best ways to increase your aerobic capacity. But you need to have a baseline decent aerobic status before doinng intervals.

Good luck with your training. No matter what yuor goals are.