Target Heart Rate?
 

In my PE class at school, my teachers have us get our heart rate between 150-180 for 25 minutes straight.
I had orientation at my new gym a few days ago, and the trainer there calculated my target heart rate to be 102-106.
Yikes! That's a huge difference!
I told her about my school, and she said that it's way too high and they shouldn't be making kids who aren't active have it up that high. (She changed my heart rate to the intermediate level, which is 125-130.) I laughed and decided to tell that to my PE teachers when I go back on Monday.
I decided to try this new THR, but when I got it there, I was only on level 1.5 on the treadmill, and wasn't sweating at all during the whole 25 minutes I was on it.
When I got home, I calculated the advanced THR for me, but that still was less than what I do at school.

I think there's something wrong with how your gym calculated your target heart rate. A rate of 102 - 106 would be fine for someone who's maybe 70 years old or a cardiac rehab patient. And it doesn't sound like you are either one of those!

Here's a quick and easy way you can estimate it for yourself:

Take your age and subtract it from 220. That number is your maximum heart rate.

65 - 75% of your max HR is low intensity exercise.

75 - 85% of your max HR is moderate intensity exercise.

85 - 90% of your max HR is high intensity exercise.

Do your school's numbers match up with the formula, above?

Look up a karnoven method calculator, it's more accurate. It takes into account age, sex, and resting heart rate. I agree the first calculation is way off. im 30, resting heart rate between 60 and 65, so my aerobic range is anywhere from 130-165 ish

125 is a very easy walk for me (think it's less than 60%, not sure don't have the chart in front of me. Intermediate is in the 150s, and all out running is in the 160s-low 170s

I always aim for an average of 75% of max while I'm working out. A lot of people seem to think you should stay in the "fat burning zone" which is supposed to be the low intensity Meg mentioned. I think low intensity is a lotta hooey when the plan is to burn calories. The higher your heart rate the more calories you are burning. For me 75% is something I can do for an hour without dying. :D

PE usually means highschool, maybe college so....yeah, the pe at school sounds about right on target 150-180, heck I am 37 and I consider that to be MY working hr range, the only time I go lower than 150 is on very very long runs (plan to be out there 2+ hours) and then I am around 140

102- 106 is way too low, and too tight a range.

If you are ABLE to do 25 min straight at the higher heart rates then it is the right range.

Perceived exertion is MUCH more accurate. At the range the trainer recommended, you didnt feel you were working hard enough....and you werent.