Those numbers are REALLY general, and are based on averages. They don't include your current weight, etc.
It's impossible to guess without an HRM to measure it, but 166 sounds reasonable for a 24 minute workout, especially when you've been doing them long enough that your body might have adapted.
Writer, mother, wife, and breadwinner. I love to run, but running doesn't love me, so I'm switching to my low-impact bike.
I'm not pregnant, just fat: My blog. fatnotpregnant.blogspot.com/
| current weight: 185.0