Was this the right approach to my cardio

[clubbinkid]

1st day with a polar heart rate monitor wanted too keep HR between 65%-75% so i can preserve muscle shred the fat

i did 35min 5min warm up 30 min light running on the mill

When my heart rate would get up to about 75% i would lower the intensity and when it was down near 65% i would raise it up to keep my self between the 65-70% range is this the right approach

[clubbinkid]

can some tell me how this is

[Soldier of Misfortune]

The range of 65-75 is correct for fat burning. The method of raising HR to max effective and then dropping, then raising and dropping, repeating is called Fartlek training, also used with hills. You can also get it in the good range and keep it there as well. 20min is the minimum for optimal fat buring, 45 is better however.