Is a low resting HR a good indicator of fitness? Two weeks ago, I measured mine with my Garmin Forerunner 305 at 48 bpm, and last week during a physical, the blood pressure cuff measured my resting HR at 47 bpm. Is this good, or can I improve?

Nobody can say but you if that is a good or bad resting HR. If it used to be 65, then yes, you have improved a lot. If you just started getting fit, you can't say, "Oh, I must be fit because I have the same RHR as my friend who has been cycling for 10 years," because everyone is different. It does change as your fitness improves, however, so unless you are in the TdF, there would always be room for improvement.

My rest hr is 43 bpm. I am very fit so this is good for me.

43?! Medic!

yea but it varies for everyone. You need to compare it over time, and see if there is a decrease. But generally, 47 is pretty good.

I remember in my biology class we measured our resting heart rate. While lying down I got mine to 39...my partner was way out of shape and his resting HR was 57. I couldn't help but laugh.

normal / healthy is considered 60-80. Anything under 60 is considered athlete heartbeat. So yes, 49 is good.

Last time I had a physical the nurse took mine 3 times because it was 51 the first time. Then she ended up with 49 and 49. I guess I was nervous the first time, she was pretty cute. She asked if I was a runner. I just laughed and said "not really, I'm a triathlete". Felt like a badass for a few minutes.

My resting heartrate is 4 beats per day. Occasionally, the day after a hard workout I get 5 or 6 beats, but that's really about it. :-P

How about this one? In the middle of my eye opperation the Doc kept telling the nurse to watch the anesthesia levals ( the alarm triggers at 40 and under), she had to keep reminding him, that I insisted on no anesthesia, and that I was training for a triathlon. The Doc chilled some, when I told yes no drugs, I 'm just a relaxed type of person.