"Healthy Living" brand HRM help PLEASE!!!!

okay so i have a healthy living brand HRM(i think since the only indication of a brand or name is that) so i finally got the user profile programmed now idk how to figure out my lower and upper heart rate(since quite honestly im not sure exactly what it means) it has pictures tht helped with the user profile but doesnt say how to get the upper n lower (the instructions are crap) lol so if you could be so kind to help me i would really appreciate it. thanks in advance.
-Christine Marie