Your ambient heart rate is the number you are getting sitting at your computer or relaxing during the day. It's a great indicator of your well being if that number is low or close to your resting heart rate. Most people aren't comfortable wearing a monitor to bed. you can get your resting number by documenting your lowest number first thing in the morning before getting out of bed and before the alarm clock goes off. Look for the same number several mornings in a row. Overtraining, illness, alcohol and stress can effect your number. Once you get a consistent number you can use this as your resting heart rate. Your goal should be to lower it.