so it gose somthing like that...

208-(your ageX0.7)=MHR , your max HR will be 191PBM
assuiming your Heart rate rest is somthing like 60 BPM 
... 191-60= 131BPM...(heart rate reserve)
[size=18:a56cc947c2][color=red:a56cc947c2]your working heart rate is (131X0.70)+60= 150BPM [/color:a56cc947c2][/size:a56cc947c2](sepend on your goals!)
o.k....
your BMI (body mass index) is 1.92X1.92/87kg =23 that is very good
so you don't need to loose wight!
if you wanna improve your runing skills, time and your general physical fitness...
here is what you need to do.

keep running 3-4 times a week. 2-3 work out run without stoping around the puls of 150BPM
1-2 times should be