Resting HR 45

It can't hurt to have it checked out, can it? I mean, wouldn't you rather know now if something isn't quite right until later, when it might be too late?

If you're not an athlete who does a lot of endurance distance, I would get it checked out. That heart rate is normal for marathon runners and distance swimmers, but likely on the low side for any other given person. Going to the doctor could be a waste of time or it could save your life.

I'm not much of a triathlete yet, but mine hovers around 50 in the middle of the day and no doubt drops into the 40's at night.  If you don't have symptoms, there's not much of a workup to do.

my friend was in ICU until his dr was like wait he is a runner get him out of there. He runs alot so maybe that has something to do with it though. sounds like more so than you but I proibabl getting down to 50 myself.

I'm 38 years old and was up until recently 50+ lbs overweight. I've never been more than a weekend warrior and just recently brought my 10Km time below 60 minutes. I have had a low resting HR (44-52) all through high school and university without ever thinking anything about it.
I started triathlons last year and 6 months later changed life insurance provider. The new insurance company insisted that I go through a battery of tests to make sure that the resting heart rate was nothing "serious" that they may have to pay for later on in my life. The tests showed nothing and was given a clean bill of health by many specialists.

After a year of training for tris and marathons, my resting heart rate is now as low as 35bpm and the 24 hour monitor that I had to wear recently showed my heart slowing to below 30bpm during sleeping periods.

I was at the hospital for minor surgery last month and the nurse wouldn't discharge me as my HR was "too low". I explained to her that it had recently been completly checked out and that she should call my family doctor... Long story short, she let me go.

All this to say that a low HR can be just fine if your blood pressure is normal. I'm living proof.
I'm sure that there are also many bad things that a low HR could indicate so I would suggest that you have it checked out to make sure it's nothing seriour.

Questionfor you: What is your max HR/lactic threshold level?
My max Hr running is 165bpm, swimming is 145bpm and bycling is also 145 bpm. Anything above these numbers and I quickly "burn out/bonk". I'm interested in knowing if your resting HR has any correlation to your maximum HR?

When I am in shape my RHR is around 38 and no doubt drops lower at night when I sleep.

You are a stud no need to get the ticker checked out. A little brady is good in a well tuned body.

Its probably fine since you are athletic but if it will make and and your wife sleep better at night no harm done to get checked. 

mine is around that in the morning and sometimes below 40 and i *did* get it checked. nothing wrong, just in pretty good shape.